I'm having trouble deciphering what exactly you're asking.
The iPad does not have a camera at all. Someday it will *probably* have a front-facing camera for Facetime, but that day could be quite a long way off; the demand for the iPad is huge and will accelerate with the release of iOS 4.1 and the holiday buying season; I do not see much chance of the iPad gaining some of the iPhone 4's coolest hardware features (retina display, facetime) till the next revision, which I *personally* expect will be next April. Nobody knows this for certain, including me.
As for your second question (again not sure what you're actually asking), cell phone bandwidth is highly constricted by comparison to broadband bandwidth. So don't expect to see FaceTime for 3G users for a long time if ever (by the time they make that happen, 4G will be deployed en masse).
Facetime, as it works with iPhone 4s (and probably the next iPod Touch) or iChat/Skype (for computers), works best with the higher bandwidth of wifi, and that will probably remain the case for the foreseeable future. I've seen hacks (and other phones) that enable video calling on 3G, but not only don't they work as reliably or well as Facetime, they wouldn't work at all if millions of 3G customers were using it.
Apple would rather hold back a feature that's cool but doesn't work with reliable excellence than move forward with something not quite finished. That's why I don't think video calling a la FaceTime will be available on cell networks anytime soon.
One last thought: some of us have been waiting for video calling to work like Facetime does for over 40 years. I *literally* got a demo of video calling when I was in grade school. The fact that its here *at all* is such a miracle, I think I can manage to wait a year or three for the infrastructure to develop a bit more to handle demand. Patience, young padawan.