Comment 2 for bug 348494

this is the intended behavior. Cheese is one of the appications in the maximus exclude list (apps listed will not be maximized), which is a gconf key set by the package ubuntu-netbook-remix-default-settings package in Jaunty:
/apps/maximus/exclude_class [Totem,Cheese]

The reasoning for this may be legacy. In hardy, cheese UI layout did not fill available space in full screen mode, iirc. Also one of the oem customers asked for it to not be fullscreen. This can be revisted for Jaunty if people feel it should be fullscreen by default.