I didn't, but I got a quick summary of it first and I think that helped. The movie is pretty well laid out for the lay person and I didn't have any real problems following along. Main thing to remember is that it's about DYSFUNCTIONAL super heroes, and that it takes place in an AU version of the 1980s. Oh, and to keep and open mind through the first bit which is a bit confusing. It all resolves itself into a plot quickly enough to keep you watching.

I really, really, really want to read the novel now that I've seen it, just to see what difference there are. My room mate tells me that there aren't many, but that the pre-credits sequence is explained better.