I'm not sure where else to post this so that others may learn from my perils.
I'm using a new-ish model of the Microsoft LifeCam Studio (Q2F-00015) under Windows 8, 64bit, OpenCV 2.4.7 (either C++ or Python).
I can not change the frame size to anything other than 640x480 unless I uninstall the corresponding LifeCam software from Microsoft (ending up with adjustable frame size, but unable to alter all other parameters, like auto-focus.).
I have not encountered these issues with older models of the camera/Windows 7.