Why? Marketing for IM will give it a much wider audience base, both child and adult, it's something new etc.
TIH is quite new, and has all the negative parts HULK in mind, so they can avoid the bad points in the last movie. It has a decent director and great cast, including some nice information about the writing.
It won't be doing the crappy origin formula like most other comic book films etc.
The story is a much better one, Banner's story has yet to be told properly on the big screen yet, and the psychological battle etc with this director and this lead man is simply a great joy.
Hellboy, Del Toro is a masterful director, Ron Perlman is the best piece of casting for any CB movie so far, and his performance was brilliant, not too mention the rest of the cast from the first. A much better plot, after the origin is dealt with(even though the origin in hellboy was rather impressive in comparison to most). The level of subtlty actually gives the audience credit and lets them fill in a few blanks etc and takes much better advantage of how direction can add extra layers.
TDK, a director I don't like, Ledger as a character who I do not think he can handle, not too mention the way in which the character is being represented, Bale's not so hot performance from the previous movie. The market for it isn't even as big as IM, because it's going for the more mature route etc.
