The mouse for the Intuos4 tablet has the same black tones as the tablet itself. It’s a little small in the hand but otherwise it feels fine. The mouse supports five different "clicks" – normal left and right, one above the track wheel and one below the track wheel, and the track wheel itself. The left and right buttons map as you’d expect. The buttons above and below the track wheel are "forward" and "backward" buttons. You would probably use them most in a web browser. I don’t know how useful they will be for me – they represent a significant change to the way I think about interfacing with my computer.
The track wheel acts as a normal scroll device but if you "click" the wheel it brings up the Mac’s dashboard – all those widget applets that you probably installed and forgot about.
Like the pen, you can re-configure the setting of each of the clicks to be whatever you want. In my case, one of the first things I did was to disable the track wheel click ’cause it was making me nuts.
Like the pen, the mouse moves smoothly across the tablet’s surface. A light pressure is sufficient. And as you would expect, you can configure the acceleration and speed of the mouse to fit your personal style. The speed of the track wheel is also configurable.