I read that and immediately had to go check it out.

For any other Unix users out there, the new, separate, middle mouse button seems to be about the size of a grain of rice.

So nevermind.

FWIW, I'm now using a Contour Mouse, solely because it has three damned buttons. The scrollwheel on the side is actually pretty nice, too. I do not have any (or very few) carpal tunnel problems. If you're in the same boat, ignore their sizing chart and get the smallest one. It's still a little too big, but the others are just freaking massive.