Yes the source is available at https://code.google.com/p/okcupid-pidg...svn%2Ftrunk
I've made the changes in SVN to fix the server-side change of the random buddies, but I haven't yet built a new Adium plugin, sorry :(

Unfortunately not, the Skype api doesn't tell us whether they're mobile users or not

Could you not include the necessary files in the adiumplugin resources?

Yep, if you have a look through the comments here and at the issue tracker on googlecode, it's a long standing issue. I could really do with a hand to fix it as the same code works fine in other clients eg Pidgin. If you look at your blist.xml file you'll notice the buddy being added multiple times. It's as if Adium forgets that the buddy is already on the buddy list when it restarts and just adds them to the end of the buddy list again.

Unfortunately with the most recent version of Skype for osx, some people are missing some of their messages. Not entirely sure what's going on yet but if you could email me a debug log from Adium with some missed messages we might be able to track it down.