The reason it's more obvious in video games is the general lack of motion blur. A game looks terrible at 24fps because there's no blur to imply the motion inbetween the frames, but movies have a lot of motion blur, which is what gives that signature film look. A movie at 48fps will probably look like a movie does on a newer 120/240hz TV with whatever they call that fancy frame interpolation.
A film at 48fps will have a very different look to a film at 24fps. I know a lot of people turn off the smoothing feature on new TVs because they prefer the classic 24fps look, because that's what they're used to. It will be interesting to see how the majority feels about this when it comes out.