So I seem to be on a bit of a Batman kick at the moment. I've been fiddling about with the challenge mode in Arkham Asylum, I watched Batman Begins for the first time in yonks the other day and plan to follow it up with The Dark Knight soon, and last week I even dreamt I was the man himself.
I'm pretty sure this has been observed before now, but I reckon the two most likely villains to appear in Nolan's next Batpic will be the Riddler and Harley Quinn, due to the way that each villain is really being marked up as different sides of Bats' personality and/or modus operandi. Observe:
Begins had Scarecrow (fear) and Ra's al Ghul (deception). Both also involved symbolism.
Knight had Joker (theatricality) and Two-Face (dual identities). Both also involved madness.
The next one will have Riddler (intelligence) and Harley (obsession). Both also involve a certain "look-at-me" mentality.
Like I say, it's surely been pointed out before. But when it happens, I totally called it.
(Or alternatively the series will go off on a complete tangent and Man-Bat and Killer Moth will be the bad guys.)