I just got a moshi clearguard from www.moshimonde.com, and I gotta say it's awesome. Had it on from day one and my uMBP's keyboard looks brand new when I take it off. It's extremely thin and see-through so you don't really notice it when it's on. Easy to take off and clean. Really a must have, can't see how I did without one before.
That Moshi cleargaurd looks fantastic, especially since I splashed a little water on my kb yesterday. However, I think I read in the mac manual that the keyboard serves as a vent? wouldn't covering with that cleargaurd cause overheating problems? Just curious.
Out of curiosity, does the trackpad also suffer from wear and tear?