Google released their talk service today, but there isn't an ability for server to server communications -- basically destroying a large part of the jabber concept.
The company is also committed to working with other service providers to create a federation model that enables users on any member network to talk to users on any other member network in a secure and abuse-free manner. Google is currently working with EarthLink to federate with their Vling communications service and with Sipphone on federating their Gizmo Project.
I hope this isn't what they hope to do to email someday -- that you have to 'federate' and be blessed before talking to their users. I've already got services that force me to login to talk to users, AIM and ICQ -- and they already have a pile of features. This is the whole worry of either free speech isn't good or that the protocol has a high likelyhood of abuse. In either case its a lame excuse.
Considering the new Blogger 'flag' feature, I've got the feeling its a free speech issue -- they want to protect people from abuse. Personally, I would hate to have to write up agreements with each xmpp/jabber provider to be able to talk to their users through a local server. Imagine if we had to do that for email!
Also -- Phone communications is 'cheap enough' that people just use their cell phones to do it. VoIP will be coming as UMA to cell phones anyhow at fairly low cost. International communications will still be a special category for voip, but I don't think that the voice feature on talk.google.com is that big of a deal.
