It was inevitable that Capcom would bring Marvel vs. Capcom 2 to the App Store. Enough people are going to pay up to make the port a success, despite our obligatory grumbling about games like this not translating particularly well to touch-screen controls.
The price hasn't been listed yet, but the company does have a release date for North America and Europe; it's right around the corner: April 25, 2012. Marvel vs. Capcom 2 for iOS will have the full roster of characters and seemingly all of the other features you'd expect to be included. I suppose that's something.