Finally concrete clues seem to emerge on a version of iPhone and, perhaps, even iPod with video chat: strings of code that clearly point in this direction. The small (but perhaps not too much) scoop of 9to5 Mac that publishes images that, if confirmed, are truly unequivocal.
In one of them taken from the latest Software Developer Kit, you can see a series of icons taken from the human interface of the telephone section. Among them, two are the 'indicted'; in the first called AcceptVideo we see a device with a sort of camera in action, in the second the barred device and the name DeclineOrEndVideo. Finally, in a subsequent image concerning strings of code, the wording VideoChat is clearly read.
As mentioned, the clues are placed in the development kit for iPhone, but for a few weeks the utility package also intended to create programs for iPad and also contains a simulator for the tablet. It cannot therefore be excluded that video chat is also intended (or, less likely, only) for this second device.
The hypothesis of a video chat system on the iPhone using a front camera in circulation for some time, but Apple has always held back developments in this direction, probably for reasons of hardware requests and for the particularities of the operating system that is currently not multitasking. The iChat port, which will surely be the tool used by Apple for chatting on the iPhone, hardly available in the absence of the possibility of running multiple programs at the same time, even if push technology would allow you to take an alternative route. The launch of a new iPhone model and perhaps of a multitaskting operating system could allow to take a new and more decisive way by opening the perspective of a video chat also on Apple devices.
As for iPad, there are clues that derive from images of the edge of the device where you clearly notice a hole that could not have been done other than for a camera. In a second photo of Jobs holding iPad, he seems to see, then, a camera in the frame. On the iPhone the indiscretions are wasted but nobody ever managed to provide convincing indiscretions on a version with camera even if a photo of the front of the alleged fourth version, longer than the current one, could suggest that the more generous edge is aimed at hosting the front camera.
Most likely to have some other solid clues you will have to wait for the presentation of the new version of the operating system for iPhone. Some hypotheses can be made about what will happen, but between mid and late March, perhaps coinciding with the launch of iPad, it may be the right time. Last year for example iPhone Os 3.0 was unveiled on March 17th.