Firefox Fitt's law correct

Kudos to firefox for following Fitts law of UI design correctly, at least under Windows.

First, maximize the firefox window. Go to the left hand edge of the screen by the back button. Notice you can activate "Back" even with the mouse cursor pressed up against the edge of the screen. Similarly, you can hit the tab-close "X" button againt the right edge of the screen. Also the "File" menu header and the firefox homepage shortcut (but not the File menu contents).

IExplore, on the other hand, does everything wrong. The back button, the file menu are all surrounded by 1 pixel edges that are inactive.

The WinXP UI, especially the start menu button, taskbar, position of the window close "X", expanded title bar and window manipulation buttons, expanded window-resize gripper in the lower right hand corner are all well designed. However, the contents of the start menu itslf (left column) do not lie against the left edge of the screen.

It's interesting that there is (correctly) no separation between the close and maximize buttons, but there is a two pixel gap between the active regions of the minimize and maximize buttons.