Good point. Indeed, I was reading into one of those just the other day -- the notion that our world is basically a single instance of a 3-space brane in a larger 11-space, and that it appears that 3-spaces just happen to be much more *stable* than most of the other possible branes. (I do want to find out more on that one, to understand the logic of why 3-space and 7-space are believed to be less susceptible to destruction than the others.)

Being fond of Many-Worlds, I tend to over-focus on it. But you're quite correct that the Anthropic Principle works for any scenario that has many potential "universes" in it...