Thanks to Blade, X-men and The Avengers, Comic book movies make a LOT of money. A lot of people like them, whether they are comic book fans or not. Even the movies are exposing readers new or old to their comics.

All of this is fine and all, but comics and movies are two separate things.
Whilst the comics and movies could probably benefit from the mainstream audience, the stories and characters should be led by the comics, not the movies. Comic books can do much more than movies. But you know what, the real reason why comic book movies are so popular is because we the fans are excited to see a Hollywood movie based from a popular comic book or video game and thanks to the 21st century, we can't wait to see what kind of special effects will be used in that movie. Just because The Avengers got over a billion dollars in the box office, doesn't mean that the only way to get readers to buy your comics is to make them like the movies. When movie uses the source material from a comic book it's get liked by all; when a comic book tries to milk or copy the success of a movie it makes people cynical.

Even the new TV shows from Marvel exist for the sole purpose of advertising the cinematic Marvel Universe.