Skype 2.0 is out with the possibility of [url=http://www.skype.com]video conferences[/url]!
But - Skype is proprietary!

Are there other possibilities?
Has anyone tried out openwengo?
It seems to be an interesting open source project.
[url]http://www.openwengo.org[/url]

Or gizmoproject?
It is Jabber based (they say on the website) but not open source.
[url]http://www.gizmoproject.com[/url]