I have my firewall set to permit google talk but for some reason it blocks video chatting. I can text chat normally when the firewall is enabled but to use the video chat plugin I have to disable the firewall. I thought video chat was a part of google talk, but if it isn’t, how can I add the video chat plugin to my firewall exceptions list?
I believe the appropriate troubleshooting page is Talk Help
If that doesn’t work, I’d suggest asking directly on the forums. There is one answer here, but it doesn’t specify which process video chat uses.
Thanks BigT. That’s actually my post on the google forums. 
Video chat is not available for the Google Talk application; at this time video chat can only be done through gmail chat from the actual gmail page (not the iGoogle widget.) Conversely, you can send files via Google Talk but not from gmail chat. I wish they’d get their shit together and make things a bit more uniform across the three platforms.