Here are some even more tantalizing pieces of information found in the latest Beta 3 iPad SDK. We've been told that if you go digging into Apple's private framework which controls the camera, the iPad SDK tests for 3 additional camera characteristics that are not found in the iPhone 3.x SDK. For comparison, Erica Sadun has a code listing of iPhone 3.x PLCameraController.h on her site. The Beta 3 iPad SDK version adds these additional test conditions for the device's capabilities.
It seems Apple built in API support to test to see if your iPad had a Front Facing Camera, Zoom and a Camera Flash. The front facing camera would, of course, be used for video chat, while Zoom and Camera Flash are often requested features for the iPhone's camera.
Further investigation (via 9to5Mac) even reveals the following icons which clearly show an interface to accept or decline a video chat: