I hate using Lync for group conversations, but I feel compelled to point out that it also works on Mac OSX. If you don't need the video/desktop sharing (which c

I hate using Lync for group conversations, but I feel compelled to point out that it also works on Mac OSX. If you don't need the video/desktop sharing (which crawls after you get more than 8 people involved), you can use Pidgin/Adium to connect to the Lync server as well. If you're looking for a more stable multi-platform chat product with video support, Ignite's Openfire works great (and also has AD integration).