A little. I think it's the popularity that's scared the crap out of a lot of people as opposed to the actual content. (I'm on the waiting list at the library for it to see what the hub-bub is, myself.)

Edit: That and the fact that at least in theory, romances are for "adults," while Twilight is marketed to teenagers. The religious are screaming about the vampires, and the non-religious are screaming about the gender roles. Strange bedfellows, eh? I'm gonna go reread Persuasion, I think. :)