After one year of hard work with WordPress Multisite and a 14 educational blogs daily updated, i can narrow (after lots of tests and mistakes) which plugins are really useful and robust enough for that kind of network blogs. I also created a plugin myself (Chief Editor) because i wasn’t able to find any doing this simple thing : see all my posts statuses across the network and all comments. I also would like to see my author performances, so i included a tab about that, inspired by the Blog Metrics plugin.
All plugins described here are the one activated on my own site, and i have no link with any plugin seller (mine is free).
Most of them are free, i’ll notice if not. Even if some of them can be quite old, they all work nicely on a WordPress Multisite 3.9 install.
Here we go:

58 really useful wordpress plugins for multisite editorial sites

1. Ada WPMS Sitewide Feed

   This plugin just gather all my blogs feeds into one big feed, so i can deliver this feed to MailChimp and automatically send new newsletters when new posts are published.

2. Admin Bar Disabler

   I don’t want my users to access the admin panel, even with no rights. It’s not their business for the moment. That’s waht this plugin does.

3. Advanced Code Editor

   Enables syntax highlighting in the integrated themes and plugins source code editors with line numbers, AutoComplete and much more. Supports PHP, HTML, CSS and JS.

4. Akismet

   Used by millions, Akismet is quite possibly the best way in the world to protect your blog from comment and trackback spam. It keeps your site protected from spam even while you sleep. To get started: 1) Click the « Activate » link to the left of this description, 2) Sign up for an Akismet API key, and 3) Go to your Akismet configuration page, and save your API key.

5. Better Plugin Compatibility Control

   Adds version compatibility info to the plugins page to inform the admin at a glance if a plugin is compatible with the current WP version.

6. Better WordPress Recent Comments

   This plugin displays recent comment lists at assigned locations. It does not add any significant load to your website. The comment list is updated on the fly when a visitor adds a comment or when you moderate one. No additional queries are needed for end-users. Some Icons by Yusuke Kamiyamane.

7. Blog Metrics

   Provides blog metrics based on the blog metrics Avinash Kaushik proposed in this post, now with a widget!

8. BruteProtect

   BruteProtect allows the millions of WordPress bloggers to work together to defeat Brute Force attacks. It keeps your site protected from brute force security attacks even while you sleep. To get started: 1) Click the « Activate » link to the left of this description, 2) Sign up for a BruteProtect API key, and 3) Go to your BruteProtect configuration page, and save your API key.

9. Chief Editor

   Manage all drafts, pending and scheduled posts and comments accross the network

10. Cimy User Manager

    Import and export users from/to CSV files, supports all WordPress profile data also Cimy User Extra Fields plug-in

11. Comment Images

    Allow your readers easily to attach an image to their comments on posts and pages.

12. Contact Form 7

    Juste une autre extension de formulaire de contact. Simple mais souple d’utilisation.

13. DeMomentSomTres Export

    DeMomentSomTres Export was build because DeMomentSomTres had a customer with a very big blog that had to be imported without only the required attachment files.

14. Featured Image In Rss Feed

    Add Feature Image to your RSS Feed.

15. Google Analytics Multisite Async

    Google Analytics Multisite Async lets the network admin collect statistics from all sites and it lets the regular site admins collect statistics from their own site. This means that statistics are collected to 2 different Analytics accounts at once, assuming that the site admin have entered an ID of course. It’s the asynchronous version of Analytics. The network admin can choose whether the site admins should be able to collect statistics or not.

16. Google News Sitemap

    Automatically generate sitemap for inclusion in Google News. Go to Settings -> Google News Sitemap for setup.

17. Improved User Search in Backend

    Improves the search for users in the backend significantly: Search for first name, last, email and more of users instead of only nicename.

18. Imsanity

    Imsanity stops insanely huge image uploads

19. Login Logo

    Drop a PNG file named login-logo.png into your wp-content directory. This simple plugin takes care of the rest, with zero configuration. Transparent backgrounds work best. Crop it tight, with a width of 312 pixels, for best results.

20. NOT FREE : Logooos WordPress plugin

    Logooos WordPress plugin.

21. NOT FREE : MailChimp Sync

    Simply integrate MailChimp with your Multisite (or regular old single user WP) site – automatically add new users to your email lists and import all your existing users.

22. More Privacy Options

    Add more privacy(visibility) options to a WordPress Multisite Network. Settings->Reading->Visibility:Network Users, Blog Members, or Admins Only. Network Settings->Network Visibility Selector: All Blogs Visible to Network Users Only or Visibility managed per blog as default.

23. Multilingual Press Free

    Run WordPress Multisite with multiple languages.

24. Multisite Enhancements

    Enhance Multisite for Network Admins with different topics

25. Multisite Language Switcher

    A simple but powerful plugin that will help you to manage the relations of your contents in a multilingual multisite-installation.

26. Multisite Plugin Manager

    The essential plugin for every multisite install! Manage plugin access permissions across your entire multisite network.

27. Multisite User Management

    Running a WordPress network? You no longer need to manually add users to each of your sites.

28. Network Shared Media

    This plugin adds a new tab to the « Add Media » window, allowing you to access media in other sites. Based on an idea of Aaron Eaton

29. NS Cloner – Site Copier

    Save loads of time with the Never Settle Cloner! NS Cloner creates a new site as an exact clone / duplicate / copy of an existing site with theme and all plugins and settings intact in just a few steps. Check out NS Cloner Pro for additional features like cloning onto existing sites and advanced Search and Replace functionality.

30. NOT FREE : NS Cloner Pro

    Save loads of time with the Never Settle Cloner! NS Cloner creates a new site as an exact clone / duplicate / copy of an existing site with theme and all plugins and settings intact in just a few steps. Check out NS Cloner Pro for additional features like cloning onto existing sites and advanced Search and Replace functionality.

31. Olevmedia Shortcodes

    Olevmedia Shortcodes plugin adds a button to editor, which provides you plenty of handy shortcodes (buttons, icons, lists, infoboxes and more)

32. Private Comment Notification Email

    Hides private details from comment notification emails, such as IP address and email.

33. Quick Page/Post Redirect Plugin

    Redirect Pages, Posts or Custom Post Types to another location quickly (for internal or external URLs). Includes individual post/page options, redirects for Custom Post types, non-existant 301 Quick Redirects (helpful for sites converted to WordPress), New Window functionality, and rel=nofollow functionality.

34. Really Simple CAPTCHA

    Really Simple CAPTCHA is a CAPTCHA module intended to be called from other plugins. It is originally created for my Contact Form 7 plugin.

35. Regenerate Thumbnails

    Allows you to regenerate all thumbnails after changing the thumbnail sizes.

36. Remove Dashboard Access

37. Reveal IDs

    Reveals hidden IDs in Admin interface that have been removed with WordPress 2.5 (formerly known as Entry IDs in Manage Posts/Pages View for WP 2.5). See options page for information.

38. RSS in Page

39. Signup Page CSS

    This plugin adds the styles/codes needed to have signup page display correctly or at least better on any theme that the main blog has selected.

40. Simple Ads Manager

    « Simple Ads Manager » is easy to use plugin providing a flexible logic of displaying advertisements. Visit SimpleLib blog for more details.

41. Smart Archives Reloaded

    An elegant and easy way to present your posts, grouped by year and month.

42. Subscribe to Comments Reloaded

    Subscribe to Comments Reloaded is a robust plugin that enables commenters to sign up for e-mail notifications. It includes a full-featured subscription manager that your commenters can use to unsubscribe to certain posts or suspend all notifications.

43. TablePress

    TablePress vous permet de créer et gérer des tableaux dans vos articles et pages, sans avoir à écrire du code HTML, et il ajoute des fonctions utiles pour vos visiteurs.

44. TablePress Extension: Row Filtering

    Extension for TablePress to filter table rows by using additional Shortcode parameters

45. TablePress Extension: Shortcode Filter from GET parameter

    Custom Extension for TablePress to use the Row Filter extension with a filter term from a $_GET parameter

46. Tako Movable Comments

    This plugin allows you to move comments from one post or page to another. You can also move comments across post types and custom post types. Just click on edit comments and move your comments through the Move Comments with Tako metabox.

47. Testimonials by Aihrus

    Testimonials by Aihrus lets you randomly slide or list selected portfolios, quotes, reviews, or text with images or videos on your WordPress site.

48. ThreeWP Activity Monitor

    Plugin to track user activity. Network aware.[hungryfeed url= »http://wordpress.org/plugins/threewp-activity-monitor/ »]

49. NOT FREE : Thumbnail Scroller (WordPress Plugin)

    This Plugin will help you to easily add a thumbnail scroller to your WordPress website or blog. The scroller is completely customizable, resizable and is compatible with all browsers and devices (iPhone, iPad and Android smartphones). You will be able to insert it in any page or post you want with an inbuilt short code generator.If you like this plugin, feel free to rate it five stars at CodeCanyon in your downloads section. If you encounter any problems please do not give a low rating but contact us first so we can help you.

50. Top Authors

    A highly customizable widget that sums the top authors(most contributing) on your blog

51. Ultimate TinyMCE

    Beef up your visual tinymce editor with a plethora of advanced options.

52. User Role Editor

    Change/add/delete WordPress user roles and capabilities.

53. W3 Total Cache

    The highest rated and most complete WordPress performance plugin. Dramatically improve the speed and user experience of your site. Add browser, page, object and database caching as well as minify and content delivery network (CDN) to WordPress.

54. WooCommerce

    Un outil de e-commerce qui vous aide à tout vendre. Magnifiquement.

55. WP-Mail-SMTP

    Reconfigures the wp_mail() function to use SMTP instead of mail() and creates an options page to manage the settings.

56. WP-PostRatings

    Adds an AJAX rating system for your WordPress blog’s post/page.

57. WPMS Site Maintenance Mode

    Provides an interface to make a WPMS network unavailable to everyone during maintenance, except the admin.

58. WP to Twitter

    Posts a Tweet when you update your WordPress blog or post to your blogroll, using your URL shortening service. Rich in features for customizing and promoting your Tweets.