Check out this rant that Greg posted about Hollywood putting the blame of comic book based movies "Needing to be grittier" in order to be successful and realistic.
Greg's absolutely right! I think of how much I loved Captain America and Ironman verses how little I liked Green Lantern. And I don't feel any of those 3 characters are gritty. A grittier Hal wouldn't have made that a better movie.
Check out his rant here at this Newsarama link.