works beautiful on my white colored painted desk, which some optical mouse failed (the old Revolution works also).
Comes with Sanyo Eneloop NiMH battery, too bad, no USB version. Better than the Revolution MX that you have to use a base charger, now has wall plug (or USB) for charging. I like the old fashion wired ones better since I don't care much about wireless and don't have to worry about recharging. Probably greener too.
Revolution near fictionless fly wheel is cool and all, it is kind of big (there is a smaller travel version, which supposedly just as good http://www.engadget.com/2010/05/25/the-mouse-aint-dead-yet-five-of-the-best-mice-reviewed/ ) still like the shape of my old classic dove bar shape (original Microsoft/IBM mouse) orange MX 510, [no longer make :( ], and the latter MX 518, G5, MX900.
Middle button is back instead of the free scroll vs. geared function as in Revolution. (loss the side wheel)
The unifying receiver is a bit too small, hard to remove in some USB arrangement. http://www.logitech.com/en-us/349/6126?pcid=6072