Iron Man and Hulk crossover

Iron Man and Hulk crossover in their movies?

http://www.aintitcool.com/node/34962

I really like this concept that Marvel is creating with its various movies. It is cool that Nick Fury (Sam Jackson) will show up in Iron Man. It looks like they actually got the person that the Ultimate Nick Fury is model after to play the role. Samuel L. Jackson gave them permission to use his likeness, probably because he’s a comic book fan. He’s certainly a better choice than David Hasselhoff.

Anyway, I hope this crossover thing is true. We could see a movie Avengers after all this. Justice League makers take note. DC comics on the other hand doesn’t seem interested in connected their movie continuities. What is wrong with DC?