Why does it seem that people prefer certain villains over certain heroes?

I was on my iPad on the IMDB (internet movie database) application and realized that the man who plays Bane (Tom Hardy) in The Dark Knight Rises has been on the top list of actors viewed since the movie came out. This was also true about the Dark Knight (2008) with Heath Ledger.

Is there something about villains that appeal to the masses that heroes do not fulfill?

I understand the rebel-clown without a cause ordeal (Joker) and exercising strength, power, and speed (Bane), but is that merely all it is?

If you liked either of these characters, why? Is there another character besides these you recognize as villain and very popular?