Apple says that Macs with a FaceTime HD camera show higher resolutions than are actually there. Way higher.
According to the Support Note, the new models (the "Early 2011" MacBook Pros and and recently released "Mid 2011" iMacs) "may display a slightly higher resolution settings" for Medium and High Resolutions in the QuickTime Inspector.
Apple appears to be offering a new meaning for "slight" in this case. The stated resolution is double the actual resolution!
The Inspector reads 640-by-480 pixels for the Medium resolution, when it's actually 320x240. Same difference with the High resolution, which is actually 640x480.