I have a laptop with an HP Truevision built-in webcam that is not working under Ubuntu 12.10. Not in Skype, not in Google Hangouts. It used to work on 12.04LTS, but then stopped working after an update.
I upgraded to 12.10 hoping that it would help, but it's still down, even though it worked fine from the Live-USB (!) and I could take my picture with it.