There are two schools of thought here, and one is prevailing...but just to play devil's advocate to Zorex:
If you had recently invested $200+ million in a solo superhero pic heavy on special effects and establishing worlds that didn't perform anywhere close to expectations, how would you feel about gambling an additional $500 mil.+ over the next three-to-five years on a green martian movie (first of all, emphasizing 'green' didn't go well already, and Martians haven't worked out so well recently), an Amazon warrior (bad TV pilot buzz hasn't helped public perception), and a speedster who may be an interesting character, but whose 'talent' really could be duplicated by another red & blue icon. Add to that a lingering audience favoritism and critical reception of a different recent interpretation of the 'winged freak, terrorizing Gotham' and what do you think?
I think one school of thought is prevailing here: why not just go for broke and invest $250 mil. in a superhero bonanza that doesn't really try to 'replicate' Marvel's The Avengers, but rather attempts to combine and reforge already-existing cultural associations with iconic characters, and based on who 'breaks out' a la Hulk, you can build from that...
'There are always...possibilities'