Obviously they had been playing with the idea of a camera. The fact that replacement parts show the location for a camera makes it obvious. Unless all those who have gotten the replacement parts are lying, but I don't see that as the case. BUT the doesn't mean the final product will have one. Most likely there was one in one during some prototype. It does seem logical that one of the devices Steve had on stage was a prototype, when designing things prototypes are often used for demos and other things.
Does this mean it will have a camera? No, not at all. Just means that they thought about it, built up some prototypes with it, and abandoned it for one reason or another -- no need to redesign everything, just remove it. BUT does this mean that there WON'T be a camera? No, not at all. The ones without the camera area in the video could be the older models; we don't know. Maybe they chose not to show it for one reason or another, like, oh say, the software wasn't ready?
We will not know until the first people get one. But I would guess that the first pads will NOT have a camera; although, it would be nice. . . I guess.