I run fink out of the unstable tree, which has the current gaim, gtk2, etc.
I keep looking for an OS X native chat client along the lines of gaim, but I keep going back to gaim. Adium is working on incorporating libgaim, but Adium's developer(s) has made some truly bizarre design decisions along the way (example: a buddy list that's nothing but a titlebar when you're not logged in - what was he smoking that day?). A lot will have to change before I can use that program. 😉
I've heard rumors of a OS X native gaim coming down the pike, but that's all it is - rumors. An e-mail to gaim's lead developer went unanswered.