My situation with the webcam is dramatic.
Feature is randomic, sometimes works sometimes no.It depends on how many USB devices I have attached (even because the webcam is an internal USB2 device, and if there are too much devices attached, the power usage goes down and windows "unplug" automatically the camera).
But...
Also downloading the latest drivers I have the same problems. The only version of working drivers was the .2.6.0.20 I think, which is not anymore on the site.
Anyway, I discovered that the only way to have the camera working is do a shutdown (not reboot, shutdown), installing again the new drivers, and having no USB devices attached.
BisonCam is the worst I saw around...