It's funny that you Americans don't even know 3G video calls... I read somewhere that all US operators simply blocked it from their networks, maybe thats why.

3G video calls are part of the phone standard - you can simply call a person an decide if the call should be voice only or video. You do not use an IM network for that, it's a phone call. You're dialing the phone number. So the "Windows netbook on a 3G netwoork" doesn't qualify as 3G voice call - unless the Windows netbook has a driver and an application that react to phone calls and support this type of video call when I dial your number on my handset.