Apparently due to the cool effects shots of Elastigirl, the powers that be at Fox have decided that they'd better step things up a notch with the Mr Fantastic sequences at the end of their movie (Mr Fantastic has stretchy superpowers just like Elastigirl). They are also rewriting/reshooting sequences related to the climax of Fantastic Four, again in apparent response to how cool the ending was in The Incredibles.
The FF movie is already costing over $100 million, but hey, what's another 20 mil between friends? :P
Personally I think this is great news and an example of movie making competitiveness helping us, the movie going public. I'm hoping that Peter Jackson's Lord of the Rings Trilogy has the same effect on future sci-fi/fantasy films.