yep it's here!
After days of speculation, Google has officially launched Google Talk!
Google Talk enables you to call or send instant messages to your friends for free–anytime, anywhere in the world. Google Talk is simple and intuitive to use. There's no clutter, no pop-ups, no unnecessary software to install. Talk also features some interesting VoIP features like Skype. Google Talk uses the Jabber protocol however instant messaging members of other clients doesn’t appear to be supported.

There's no Linux or Mac client yet, but there are guides to connecting to the protocol on iChat, Gaim, and Trillian.
http://www.lebgeeks.com/tech-read-2-1124994760.html
Been using it the day it came out :D pretty cool but the voip didn't seem to work :S. I like the simplicity of the program.
some1 add me !!! i want to try it !
Way too simple. MSN has webcam, whiteboard, games, etc... skype has nice voice features and user search... but this thing, it has nothing but type or talk... it's like MSN five years ago.
Plus it doesnt even connect... dont ask me why...
what i like is the way a conversation is held, whereby if i keep typing it only puts down my nickname once, not like msn every msg has bala bla bla says
7 months later
exactly, .. it's beautiful by it's simplicity!
a month later
I'm a bit late on the topic.. but the great thing about google talk is that it's using the jabber standard.. Which practically means anyone can write an im client and be compatible with gtalk.. putting an end to the im incompatibilites... an old dream..