Was just checking out a plugin I’ve (shamefully) never seen before called Post Type Switcher, by the illustrious JJJ. It’s an awesome plugin, and one I’m going to keep around and use, but that’s beside the point right now.
While checking out the plugin stats tab, I noticed an odd slice of the “Active Versions” pie chart, with about 12.5% of active versions of the plugin at version 999.3. See here:

So of course it’s odd to see a version like that — JJJ said he doesn’t know anything about that version number, either — but it’s another thing for it to be the version on over 2,000 active installs of the plugin.
So what I’m wondering is, how did this happen? I’m guessing someone bumped the version number up to avoid updates, but wherever they’ve done it, they’ve done it distinctively across a large number of installs. Does anyone have any ideas on this one? It’s just weird, is all.
Or, even better: which one of you is causing that odd version stat yourself?
I’m not the only one who does that?
Looks like they hacked 0.3 and added 999 to keep clients from clobbering their changes, maybe on a large multisite install?
Does the repo count multisite installs as multiple plugin installs?
Not the only one, nope
My gut says that a network is counted as one plugin install, but I’ll double-check on that one.