I have heard it said several times and in several places that followers of Islam prefer to be referred to as "Muslim" rather than "Moslem," but no one ever explained the why of it to me. In the course of chasing down a quiz that asks you to consider the rhetorical similarities of Messrs. Falwell, Robertson, and bin Laden, I found the answer here. It also provides a great excuse for why I could never spell the name of that guy who runs Libya correctly either. Whew.