Here at the job, we’re running what is now a good-sized implementation of the WordPress multi-site platform. At over
110 500 blogs so far, and more requests coming in all the time, some plugins and themes are bubbling to the surface. Maybe this will help you sort through the maze of options and find the one that does what you need without a lot of headache.
I originally put this up in September, 2011. Of course a lot has changed, so here’s a more up-to-date sampling.
Here’s a few we run network-wide:
Akismet. It’s blocked 2,279 spam comments just on our primary. Enough said.
Black Studio Touch Dropdown Menu For many themes, makes dropdown menus possible on touch-screen devices.
WordPress Zero Spam. Utter magic.
Google Analytics +. Makes it easy to add tracking codes to any of our network blogs, without manhandling the templates. Also good because you can run the same blog against two accounts — a departmental one and an institutional one, for example.
Style Press. It would be madness to try and develop child themes for every single instance of twentyten, just so that the headlines could be a different color. Style Press is network-activated so that each blog has a certain amount of control over their look. StylePress has passed into the realm of unmaintained plugins. My Custom CSS does all of that along with color-coded classes and rules.
User Role Editor. Likewise, it would be insane to let a single blog’s administrator be able to install, edit or remove plugins and themes. This one lets me create a “safe” administrator role, so that they can manage all the things in their own blog without doing harm to anyone else’s.
wpDirAuth lets us authenticate using our Active Directory server. There are other plugins that do the same, but this one was comprehensible to someone like me who isn’t an LDAP master.
WordPress Network Theme Stats gives you a rundown on which blogs are using which themes. Helpful if you need to do surgery or an update, so you know who — if anyone — is going to be affected.
cets_blog_defaults (Now called “New Blog Defaults”) so you don’t have to set the time zone, comment rules, default theme and a hundred other little items on your checklist when you make a new blog.
Other Site-By-Site Additions
Active Plugins does something similar to Network Theme Stats, only for plugins.
Advanced Custom Field Widget lets you do an amazing number of things with your custom fields. It’s got a steep learning curve, as most good power tools do, but it does things that only re-coding your template would otherwise allow.
Contact Form 7 The easiest-to-use form builder we’ve found. It handles all kinds of input, and lets you customize the responses. There’s also a second plugin that will write the responses to your database.
3Pagination replaces the simple previous/next built-in pagination with a nicer    .. style set of links.
Comment Indexer and Recent Comments Widget These two plugins let the multi-site superuser keep spammy comments off of everyone’s blog. Really important because not everyone can tell when someone saying “nice post” is really just doing a clickbait job.
Shutter Reloaded is a lovely image viewer. Activate it, and all your images — whether in a gallery or just embedded in a post — become clickable links that show the full-size image in a shadowbox. A picture (so to speak) is worth a thousand words. It does this — click on the image:
wp-mail-smtp. Our setup here at work allows mail to go out only from one server. Sendmail doesn’t work, so WordPress needs a way to get mail out via that SMTP server. This one is easy to configure and works reliably, and that works for me.
Private Only Restricts visibility of a blog to registered users only.
Other Power Tools
You don’t need these all that often, and can be activated and deactivated as necessary.
search-regex is a dangerously powerful tool that lets you find and replace text blog-wide using regular expressions. When we originally ported over some 120 Movable Type blogs, all the embedded links had to change to fit the new file structure, and this made it possible.
RSS Importer, Movable Type and TypePad Importer Switching from one platform to another? This let us bring over the Movable Type blogs by exporting their RSS feeds, and then re-importing them.
Post Type Switcher if you import content, for example, it will come over as posts. But what if you wanted them to be pages? This does the work for you.
Add Cloned Sites for WPMU One project that comes up is to set up an arbitrary number of blogs for students in a class. They’re all going to have the same pages, menus, subtitles and pre-written content. Use this plugin to create one master, then roll out identical copies.
Redirection lets you do the equivalent of a complicated .htaccess or httpd.conf redirection file. If you’ve moved things around, you’ll want this.
Well that’s enough, the ones we use all the time.
Update 2: Caching. Some kind of caching. One of our work sites was coming in at an average of 1049.56 ms (over the course of a week). We installed WP Super Cache and new times are coming in between 249 and 315 ms.