Now, this might not look particularely interesting... but read it again. Then think about it. Again.
The Jabber Foundation has released JEP-0166 (Jingle) to interface XMPP with SIP and H.323 (also known as "Voice over IP").
At the same time, Google has released libjingle, a JEP-0166 and JEP-0167 (Jingle-Audio) implementation that is used by Google Talk.
It's published under BSD License (and, hence, usable in OpenSource and closed source applications).
Yes, that means that OpenSource Jabber/IM clients can now implement Video+Voice support that is compatible with Google Talk. Imagine the potential.
The Psi team already announced that they're starting to add Jingle support to their Jabber client, and same goes for GAIM.
MSN and Skype, with a big, successful and hyped business like Google behing Jingle, you're going to be taken for a rough ride.