I have a few qualms with the Mighty Mouse...
Second, the scroll ball gets dirty and refuses to scroll in certain directions, necessitating a cleaning. Dirty mouse balls?! I thought we were past this years ago.
Third, the right-click. I strongly feel I should not have to adapt the way I use my mouse just so that one manufacturor can stick with its arbitrary wish to have a mouse that appears to only have one button. As it is, about 30% of the time I right-click, I accidentally left-click instead, and often that causes counterproductive things to happen (like I shift-click a bunch of items in a selection to perform an action, accidentally left-click and lose the selection.. doh!)