Apple released a new mouse the other day, and I had a quick play with it today in an Apple store. It's really pretty, but I don't think it's very good.
There is no scroll wheel, so in order to scroll you have to drag your finger across the surface. This is kind of tiring. Laptops with trackpads also make you drag your finger around, but when you're using a trackpad your hand is oriented so you can move your whole hand rather than just the tip of your finger, and that makes it a lot easier.
There are no buttons on the top, so to click you push the whole mouse down. To right click you press the right side of the mouse down, and to left click you push the left side down. But if you have fingers on both sides of the mouse when you push one side down, it always registers as a left click. To right click you have to lift your left-button finger off the mouse. This is really annoying.
So yeah, don't buy Apple mice.