I'm going for PC, because of the TES CS, and I have better reflexes and control on the computer, when it comes to this stuff.
I think, since the graphics are so much better (than Morrowind) in Oblivion, and the CS will include more flexibility in altering faces, I will attempt to try to learn to use the CS. Hopefully, the CS is more user-friendly.
I have Morrowind on PC and X-Box, but I prefer the PC version, because, when I played the X-Box one, the loading time was too, too
slow compared to my somewhat already slow loading time on my PC version. And the control scheme for the X-Box was much harder for me to get a grip on.
Besides, I never really play that X-Box that much anyway. (I prefer PS2 and GC).
But, in the end, it really depends on the person. Some people feel more comfortable with a controller, and others feel more comfortable with a keyboard. I'm sure Oblivion will be great on both versions.