Apple unveiled the new Magic Mouse on Tuesday. The first Magic Mouse reviews have been published and it looks like the new Apple mouse is getting a mixed reception.
The overall consensus is still that the Magic Mouse is the best mouse Apple ever made, but there are ergonomic issues that according to CNET does not make it a full desktop mouse. They see the Magic Mouse more a portable Laptop companion.
Gizmodo is more upbeat about the Magic Mouse in their review, but also mentions that the mouse is not really ergonomic as it is too narrow.

To have gestures support on a mouse is clearly a great idea, but a mouse needs to have a certain size to make your hand feel comfortable. On the other hand so many Apple users lived with the tiny and awkward Mighty Mouse for years.

Magic Mouse comes standard with the new iMac and will be available as a Mac accessory at $69.