Not too big a change, but nice none the less. Google Talk has been updated, and now has a couple new features. The biggest are the support for user images (avatars, as some in the know might call them), and themes. I haven’t got into it yet, but I’m interested in finding out if the themes are customizable beyond the set they give you... like simple CSS-ing? That would be neat!
Another addition is that you can now get Google Talk for your Blackberry... useful when your carrying your PDA/cellphone and you want to contact someone... wait a minute...