I just noticed that you can double tap the Magic Mouse with two fingers to enter Mission Control. If that feature was present before 10.7.2 it slipped under my radar. I find this new feature kinda handy; it speeds my workflow quite a bit.
[crarko adds: I don't have a Magic Mouse to try this; I'm guessing it's analogous to the two-finger swipe up with the trackpad. Try it out and let us know if it worked; also if it's around in 10.7.1 or earlier.]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20111014003243183