5. Aquaman - Paul Walker
Paul Walker might be better known for his role in The Fast and The Furious franchise, but not only has he proven he can act (Running Scared) he's also an accomplished swimmer (he majored in Marine Biology). He's been rumoured for the part before too. His performance in Into The Blue showed he could comfortably pull off shooting underwater scenes and he also has the physique to fit the role. Aquaman will possibly spend most of the film topless so the last thing DC need to do is cast an outright pretty boy. Even though Walker fits that description, he has a rugged enough look to pull it off. Including Aquaman could prove to be one of the most difficult obstacles for DC and Warner Bros. but as a leading member of the JLA, Arthur Curry is as important as any other hero. Even though he is the most ridiculed superhero, I think it's about time he was shown some respect. Geoff John's New 52 series has breathed new life into the king of Atlantis so the writers would be wise to follow some of those outlines. While not in the rumoured official roster line-up, it's a safe bet he'll be included in some capacity.
Notable Mentions: Josh Holloway, Sam Worthington, Taylor Kitsch.