To me, the maxim top 100 or whatever isn't all that attractive. Mind you, I've got a warped sexual drive without boobs, but I can represent many guys out there.
Megan Fox is a prime example of what I might call "bitchy" hotness. Similar to the "douchebag" hotness of males, it can be rather unattractive and more importantly unrealistic. If a naked Megan Fox barged into my room right now, I would most definitely leave. However, if she was in pj's watching adventure time on the couch without any of her social facades you can bet I'd be on her before Finn says "Mathematical!"
That being said, the context is very relevant. I feel it's more than that, but I can't quite find what it is.
What I'm trying to say is that what girls try to look like is hardly every what guys feel is the most desirable. It might get you a date and a one-night-stand, but being hot doesn't get you very far. Unless you want to act, in which case it doesn't matter how bad you are at everything else: as long as you can look like megan fox on the silver screen you can go pretty far.
then you get old and nobody likes you, I guess.