Well, I've tried it before, and could never get into it. When I think Metroid, I don't think FPS. I think platformer, period. I'll admit that the level design really surprised and impressed me, but the controls being what they were, and the fact that I'm generally terrible at first person oriented games except for the general multiplayer halo type stuff means that I couldn't enjoy the Metroid Prime games.
The only reason they moved to first person is because nobody makes proper platformers any more. I'd absolutely love to see more proper 2d platformers come out. I mean, there's enough graphical power there that they can make some very nice graphics and effects. Not to mentioon since these console sare quite a bit more powerful than the SNES/Genesis they should be able to add some stuff not typically found in an oldschool platformer, due to technical limitations/size limitations and such.
With the power of today's systems, if they really wanted to, someone could come out with something that completely redefines 2D platformers.