The webcam should be compatible with OS X. The webcam I used under OS9 is not compatible with OS X and the company that made it is not going to issue an updated driver. I could buy a third party driver for $40 but it doesn't make sense when the webcam only cost $60. I make do with it in OS9.
With that said, most new webcams do work with OS X. But check out their website before you buy one just to be on the safe side.