Critics say that film has been viewed at 24 fps for 90 years and it has worked just fine. True, but why not aim for better image quality? Filmmakers have done that since the medium was invented. It's not like film stock and lenses didn't evolve since the 1920's. They also say that higher frame rates look like soap operas shot on video. The notion that higher frame rates look cheap will for sure be proved wrong when The Hobbit and Avatar 2 premieres.
The most interesting idea comes from the conspiracy theorists that say that increasing the frame rate is a way for the big studios to produce movies with technology too expensive for independents. Following the digital revolution in filmmaking you can get camera gear that is just as good (or the same) as the equipment used by the major studios for relatively little money. Today there's no reason that there should be differences in the image quality between high and low budget films. Unless of course the major studios start shooting at 60 fps, which the indies can't afford, which is the whole point of this according to the conspiracy theory.
My view on this is that we may have to accept that. And it may not be a bad thing.
In the future, there may be a more visible difference between high and low budget movies. Hollywood blockbusters will be 60 fps and 3D, while indies will be 24 fps and 2D. There's nothing wrong with that. In the 60's, many low budget movies were still shot in black and white. It didn't make them worse than the expensive ones, although they had a clearly different look. And as always, different doesn't equal worse.