Hi,
If you can get the Yahoo IM app for Mac to work (It is still in Beta and has been for Years) then it is the only direct way.
Tokbox is a Web Browser Based Chat site that allows you to use your Camera. (It uses the Flash Plug-in)
It has the advantage in that you can link in your existing Buddy Lists.
Mebeam is a less formal site that does similar (Lees the Buddy List Linking)
The MSN App will only Video Chat if you are linked to the correct Microsoft Server (I forget the name exactly)
ProteusX and
Adium are both essentially text Based Mac Apps that can join multiple IM Services.
I believe Adium now uses a link to MeBeam to do Video Chats (I have not tested this)
See my Comments to Mackural about what is possible with GoogleTalk names.
9:29 PM Monday; October 4, 2010
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