It could well be that the high bandwidth usage of videoconferencing is too much for AT&T's network to handle. After all, it can't handle regular data traffic in cities like New York and San Francisco, so perhaps Apple is ensuring the problem doesn't exist by not providing a camera in the first place. This would be consistent with Apple's disallowing VoIP apps on the iPhone until this past fall, when AT&T said it could finally support the traffic.
Another theory: The health care industry has long been interested in tablets but has not liked the bulky, hard-to-use Windows offerings, and an Apple tablet is conceptually appealing to hospitals. However, a built-in camera would raise too many privacy issues for them to adopt the iPad. If true, that's easy to address: Apple can offer a camera-less model. In either case, Apple won't say.
iPad question No. 6: Will the iPad's internal storage be upgradable?
We do know that the iPad's internal flash memory will not be user-upgradable -- you can't just swap in a new card. But will Apple provide, or let others provide, an upgrade service for the iPad, similar to how you can have a battery replaced in an iPhone or iPod Touch by an authorized service provider? Apple won't say.
iPad question No. 7: Will the iPad allow multiple apps to run simultaneously?
The iPad has as much in common with a PC as it does with an iPhone: iPad developers can use desktop UI conventions such as menus and dialog boxes, and the bigger screen opens up the possibility of apps that can do more desktop-like things, as the bundled app shows. So iPad users will expect to be able to run multiple apps at the same time. (Some parts of the iPhone OS do run simultaneously on the iPhone and iPod Touch, but beyond those core capabilities, Apple forces apps to suspend or close when the user switches to another app, ostensibly due to memory-usage and processor-performance issues.)
Apple's use of its own processor chip, the A4, in the iPad raised the possibility of running multiple apps at once. But Apple won't say.
iPad question No. 8: Will Apple allow the use of Flash on the iPad?
Users have been complaining about the lack of Flash support since the very first iPhone three years ago. Apple has said little, though Jobs has criticized Flash for taking too many system resources and Flash Lite for being not capable enough. It's true that Flash technology is often used to create buggy, memory-sapping videos and animations -- you see that in your desktop browser all the time. But as Apple increases the peformance of its mobile devices, you'd think it'd hit a point where it can support Flash and let ill-behaved Flash files simply close the app running them.