Reviving this old thread, because today I've bought myself a Mighty Mouse. In short: It sucks. There are three distinctive problems:
1.) I feel like I'll get carpal tunnel in no time after using the mouse for only a couple of minutes. I guess I'll have to hold it differently somehow, but it just doesn't feel right. I have no problems with a bigger mouse (the oldest optical Microsoft mouse is the one I love best, actually) or a smaller mouse (a smaller MS I've bought gives me no trouble, either), but this one somehow... Well it doesn't feel right. I hope I'll get used to how it feels, because else I've just bought something to hang on the wall. (No, I won't give it away, I really like how it looks on the wall.)
2.) Drag & Drop doesn't work. So you click on a file in the Finder and start moving. If you have to move it more than, say, 400px, you have to lift the mouse. Dashboard or whatever function you have on Squeeze kicks in and drops the file. Or the click-function just goes away. Either way: Can't really drag a file from A to B. This sucks.
3.) Right-clicking. I know. You have to move the left finger in order to make the mouse notice right-clicking. I think this is what gives me that carpal tunnel feeling, really. Half of the time I forget about lifting my left finger first, I swear, do it right and almost get a cramp in my right hand. It sucks.
Really... I can't state it any differently: There was nothing _wrong_ with how other companies designed two-button mice with scroll-wheels. Apple could have even _done_ the thing with the scroll-point-thingie, but the mouse really needs two actual buttons, I believe, in order to work right. Since this is now the default mouse on new Macs, I strongly feel that Apple has to change it. I'm aware that some people like it, and I really like how it looks, too, but for now, I'm going back to my MS mouse.