In a sense, I was really hoping there was going to be something special about this mouse. When you think about it, however, the basic design has been with us for many years (just like keyboards). I guess when you find the closest thing to a perfect design (in a basic sense) there has to be a major paradigm shift and interface change to come up with something better.
Really, the only truly major changes (read: additions) that have been made to modern mice vs. those of yesteryear have been the scroll wheel and optical/laser sensors.* I would also argue that only one of those, the scroll wheel, has actually changed/augmented the way we use mice.
*There have also been interface changes, (serial, bus, USB, PS/2, etc.) but that has more to do with computer evolution, overall, and nothing to do with mice specifically.