I've been doing computer animation for 35 years, as long as it has existed. Back in the early 80's, I worked on some early 60 field-per-second animation; and I was a convert to high-frame-rate footage since then. (The opening to the PBS show NOVA was perhaps the first 60fps animation ever done.) When we started doing broadcast graphics (show openings, things like that) for TV, we naturally did them at 60fps, and that looked right as it worked with the rest of video. Finally, though, we moved into advertising, and TV advertising was (and still is) typically 24fps. And it bothered me!
But then, something changed my mind completely. We were doing an ad for Snacky, a Japanese snack food company. There was the required silly animated spokespuppet, and we modeled it and made it perform. Part of doing animation is doing the lip-sync, and the company gave us the dialogue in English to animate to. We did this, although it didn't seem right -- expecting them to give us the Japanese soundtrack eventually.
But no, it got to a couple of days before delivery, and the character was still speaking English, and we asked the customer when he came to review the work. "This is only going to be shown in Japan, right?" "Oh, yes, yes!", "And you're going to dub it into Japanese, right?" "Of course! Yes!" "But the lip sync is to an English sound track, the lips are not going to match the dialogue!" "YES! JUST LIKE ALL GOOD ANIMATION!"
Because in that day, lip-sync that was correct in Japanese meant it was low-quality domestic animation; where if the lip-sync didn't match it was high-quality American animation. Nobody can tell me that wrong lip-sync is in any way superior -- except that there were 150 million people in Japan who would see it that way instinctively and immediately.
So, I became a happy convert to 24 fps animation. I applaud Peter Jackson for his incredibly audacious experiment, and I hope he succeeds, but he has to fight the near-instinctive reaction from a lot of people who see 48 fps as video.
I think that part of the problem with The Hobbit at 48fps is that the screens are so terribly dark that you just can't appreciate the high frame rate. Your eye integrates dark scenes over a long period of time, and at 48 fps with the very very dark 3D screens, I believe that your eye smears the frames together. On Transformers III, I removed all the motion blur from the very dark scenes, because even at 24 fps they got smeary.