Nicholas Cage = Huge Fan.
Let's peruse some other huge fans who made comic book movies.
Richard Donner - Superman (1979)
Sam Raimi - Spiderman, Spiderman II
Bryan Singer - XMen, X2, Superman Returns (2006)
Robert Rodriguez - Sin City (even if you didn't like the movie, you have to admit it was a faithful adaption)
Brett Ratner - X3
Movies where fans WEREN'T involved with the movie:
Pitof - Catwoman
Julian Grant - Electra
Ang Lee - The Hulk (weird little asian guy... and he made Brokeback Mountain right after... I don't even know what to make of that)
The only exception that I can see is Daredevil, which was made with the help of huge fans (pretty much every writer for Daredevil for the last 20 years was in it, from Frank Miller to Kevin Smith), and I think the exception proves the rule.
When a fan of a genre makes a film in the genre, it's going to be a far superior film. (crossover examples- Sergio Leone and westerns, Peter Jackson and fantasy/ape movies)
-kv