When a window is maximized, Metacity removes the left/right/bottom border of the
window. This is very useful, for example in Firefox or any application with
scrollbars, because simply moving the mouse *far-enough* to the right will
position it onto the scrollbar.
Compiz doesn't remove these window decodations. As a result, moving the mouse to
the far right lands it on the window decoration. To scroll, the user needs to
delicately position the mouse to the left by 10 pixels. Quite unnecessary IMHO.
Compiz SHOULD remove the left/right/bottom window borders for maximized windows.