I am a hardcore fan of a 60fps standard across the board. But it all comes down to a simple matter of opinion if you agree with me or not.
Graphics are all-encompassing of what one sees visually. Instead of developers sacrificing a smooth gaming experience for a few higher-res textures, they could just as easily contribute more time and effort to the art design of their game (which is my strong preference). In my opinion, the frame rate has just as much to do with graphical prowess than does anything else that is on your screen.
It's a balancing act, really. If developers decide to drop frames in favor of better textures, effects, etc., they have every right to. And in that case, those guys/gals making that particular game see it as a 'better' gaming experience. So that being said, I don't think there should be a standard set in place just for people that see things the same way as myself. I do hope, though, that more developers next generation will promote a smoother gaming experience by way of higher frame rates.
I would like to note that I see a marked difference at 60fps in any and every type of game, making the experience more enjoyable no matter what I'm playing.