I can't use the Magic Mouse because it doesn't fit my human-sized man-hand: it has no palm support. And this strikes me as odd because how it looks should be extremely secondary: the only way to effectively use a mouse is to look at the screen not at the mouse, and even if you were to look at it, your hand is covering it up.
For those reasons, I find it neither aesthetically pleasing nor a joy to use. It's unfortunate that aesthetics have been merely associated with how something looks when it's just sitting there and doesn't take into account a pragmatic, active angle (not saying that that's how you associate aesthetics, brianwillis).
It has no palm support because you're not supposed to put your palm on it -- it's meant to be held by the thumb and pinkie at the sides (like the pilloried hockey-puck mouse).
If it was shaped to rest your palm on it, you wouldn't be able to use any of the multitouch features without fully removing your hand first.
And I think that may be part of the problem: I didn't find that to be a comfortable position to use the mouse even for short periods of time, having to hold my fingers and palm up and not having a resting, but still moving the mouse, position. I found it extremely hard to get fine control of positioning while clicking, I'd always end up moving the mouse slightly while clicking (incidentally, I have similar issues with the touchpad on the MacBook Pro).
For those reasons, I find it neither aesthetically pleasing nor a joy to use. It's unfortunate that aesthetics have been merely associated with how something looks when it's just sitting there and doesn't take into account a pragmatic, active angle (not saying that that's how you associate aesthetics, brianwillis).