Official Gmail Blog: Say hello to Gmail voice and video chat
The peeps at Google just launched video and voice chat from within Gmail. I really am waiting to criticize them for this move. Turns out, the app would be using H.264 encoding so external apps can choose to speak to this service. The implementation would no doubt involve a flash player on the front end. Im yet to really see an implementation of the flash player which can capture both voice and video from the client side at the same time not making the app sluggish (which im sure Googles' newest product WILL be!) .