Michael Eisner was the maniac who damaged the Disney/Pixar relationship and almost lost them. Robert Iger was named President and CEO and came in and repaired that fiasco immediately after Eisner left. Disney is a marketing machine which will push the Marvel stuff even further, and is distributing Pixar much further as well. They do have their corporate culture rules, however, I think that Marvel will still be able to keep much of their own identity - Disney will be adding their bulk to distribute them more.
There's only so much princess stuff they can do, and now they can pull in that younger male market. It will certainly be an interesting combination.
Maybe a new theme park could be planned.....Land of Marvel.....
The Spiderman ride would have people swinging between buildings.
Ironman games where you blowup as many people as you can fly over.
Fantastic Four Land: see how much heat you can take in the flame chamber...
The Disney Imagineers will have a field day for sure!