I got a chance to try out this mouse at the Apple Store this weekend and wanted to give my thoughts as to how I liked it.
When Apple announced this mouse, it was big news. Why, you ask? because it is the first two button mouse that Apple has ever produced! Apple has always insisted on one button mouses over the years. I never agreed with this philosophy of theirs. When I switched to the Mac, the first thing I did was throw a PC mouse on it so I can have the right click and scroll wheel functionality. Once you have those features, you can't live without them. OSX supports these features natively, and yet Apple didn't sell a mouse that provided these features. I always found this strange, but Apple has finally solved this oddity.
What do I think about the mouse? I have mixed feelings about it. It looks identical to the current see-through Apple mouses in shape and size, except that it is plain white plastic instead of being see-through. Other than the color change, the only noticeable difference is a very small rolling ball on the top of the mouse. The mouse works well as a mouse for general purposes - moving around, clicking, dragging etc. It is the features beyond this that have my uncertain.
The first thing I don't like about this mouse is the scroll ball. It is VERY small, almost to the point that you can't see the thing. This extremely small size makes it very hard to find with your finger and to properly roll. It is so small that scrolling any more than a short distance causes you to have to constantly roll the ball, then reposition your finger back to the beginning and roll again. Very annoying. Also, it doesn't seem to function well in diagonal directions. It works well for horizontal and vertical scrolling, but diagonal barely works. Replacing the scroll wheel with a scroll ball is an obvious improvement, but I think this ball is too small to be useful. It needs to be made bigger.
The second thing I don't like is only a minor annoyance compared to the scroll ball. The mouse does not have any visible left or right click buttons. It detects the mouse click by sensing whether your finger is on the left or the right side of the mouse. The problem is, most people, myself included tend to rest their finger on the left mouse 'button'. When you do this with the Mighty Mouse, it detects your finger resting on the left side and thinks you are trying to do a left click, even when you click the right side of the mouse! This means that in order to do a right click, you have to make sure your left finger is not resting on the mouse when you click the right mouse 'button'. It's a minor annoyance, but it's an annoyance, nontheless.
All in all, I think I'll have to pass on the Mighty Mouse. It doesn't seem to offer much new over a standard two button mouse with a scroll wheel.