From the release notes:
Addresses potential causes of “insufficient bandwidth” alerts in iChat.
If a conference doesn’t start as expected, iChat will now offer to send a report to Apple for investigation.
(video chat is one of those things that’s surprisingly useful, and surprisingly irritating. The combinations of clients and routers that actually work together in practice appears to be almost vanishingly small, and every time I’ve tried to do it, it’s driven me up the wall. The common failure in iChat AV is ‘insufficient bandwidth’ – which usually means something else entirely – though it’s also rather fond of ‘…did not respond.’)