There arent iSight drivers for Windows yet & I dont think Apple will make them available any time soon.
any updates to this? there is an uption in parallels>usb>built-in isight but i can't seem to get the webcam to work... i was hoping to be able to use the windows version of yahoo messenger as it has both voice and video capabilities
Try out this solution in the Parallels forum. Worked for me: http://forums.parallels.com/thread10334.html
The thread in the link I posted above contains a link where you c an download the Windows driver for the iSight.