Update, google sez:
We want to make IM as open as the web or email...End Update
I think that the ultimate destination is to come up with a system that is as distributed and decentralized as SMTP/email while not falling prey to the spam problems that SMTP has. We are going to test those waters first off by starting federation with a few partners and then moving on from there.
Independent journalist Om Malik on his blog at http://gigaom.com/ pointed to technical clues that suggest Google is preparing to run an instant messaging service based on an open-source system known as Jabber. Jabber technology would allow Google instant message users to connect with established IM systems that also work with Jabber, including America Online's ICQ and Apple Computer Inc.'s iChat, Malik said.