http://arstechnica.com/reviews/hardware/mightymouse.ars/3
Conclusion
When all is said and done, all of the the Apple PR on the Mighty Mouse product page is a bit much. As a poster in the Mac Ach succinctly observed, "this thing isn't as revolutionary as one may think. It's just nice to have an Apple mouse with a frickin' scroll button and right click."
To bring us back to the old HCI argument, Mac users are now debating whether Apple should be shipping these with new systems. One-button proponents are very concerned for their users and family members becoming just as confused now while using the Mac as they are on the PC with too many button choices and too many unexpected things happening on the screen.
Multibutton proponents think that, unless Apple packages it with new systems, this whole move is essentially meaningless to the gangs of geeks who are already addicted to very sophisticated multibutton mice, and that Apple is merely attempting to steal business away from companies who already sell multibutton mice independent of computer systems.
Here's my take on that subject: I think Apple should package the Mighty Mouse with new Macs. You would never know, even accidentally, that it wasn't a one-button mouse unless, well, you knew. If you click both buttons at the same time or just press on the mouse shell altogether, it acts as a left-click. If you click on the right side, you get a contextual menu. Only after loading the software and intentionally clicking on the right side does the contextual menu pop up, and that's assuming that you've changed the Mouse preferences from the default setting to allow the right-click button to do something other than left-click. This allows for a great deal of versatility for one mouse