As you can see from the announcement
here, this is pretty big news. One of the biggest complaints about the PIC (public IM) functionality of OCS is the fact that it would not interface with Jabber/Google Talk. Thankfully, that all changes today with the release of the XMPP Gateway.
On a bad note, it looks as though virtualization of this role isn't officially supported, but I am hoping that changes as time goes on and Microsoft can run the software components through the various validation tests. The other unfortunate aspect is that it cannot be co-located on an Edge server role.
All in all, a step in the right direction. They also announced that the AOL PIC license shares the same type of "free"-ness that the MSN PIC license received a few months ago. Basically if you have LCS/OCS Standard CAL with Software Assurance, the MSN and AOL PIC licenses get thrown in with the deal.