As might be expected from a show that uses an ad agency as its setting, its themes include appearances, deception, style, and perhaps most importantly, status. This makes for some interesting commentary on the role of women, minorities and gays and lesbians, though the straight white men remain, at least for the two seasons I've watched, the central focus of the show.
I won't be in a position to judge the show until I finish it, but at this juncture I will say that I find it...interesting. Like a good ad, it's drawing me in. But I'm not sure yet if I've bought the final product.