Here's a nice, easily overlooked tidbit from the release notes to the 10.4.9 update that we mentioned before: Apple has added support for USB Video Class cameras in iChat without the need of a third party driver a la iChatUSBCam from ecamm. A user in the MacRumors forums reports that the the Xbox Live Vision Camera (~$40) now works natively with the Mac. This should presumably be the case with other USB Video Class cameras as well, and while I would probably prefer a model from Logitech, the Xbox camera is widely available and relatively inexpensive. With iSights now unavailable this lends credence to the rumor of some sort of USB iSight replacements (or maybe Apple is just going to stay out of the webcam business altogether, given that iSights are built-into so many models now).
Thanks to those who sent this in!
Update: Be sure to note that iChat in 10.4.9 only works natively with USB Video Class, not every USB webcam is Video Class.