Skype just announced that its new version for iPhone/iPad/iPod and it supports video call!
You can make and receive free Skype video calls on your iPhone, iPad or iPod touch, and works over both WiFi and 3G connections.
iPhone 4, iPhone 3GS, and iPod touch 4th generation:
You can make and receive video calls if it is i0S 4.0 or above.
iPad and iPod touch 3rd generation:
You can only receive video calls and record Skype video calls.