Well it's running on the same console hardware so I don't expect the requirements will be going up at all. Right now I'm sitting on an i7 system with a 280GTX. That should hold me fine for the next few years.
Well, Bethesda claims that it'll work and look like a next-gen game.
But yeah, I'm probably going to get some new hardware for this - the question is what hardware?
Until we know the system requirements for Skyrim, I can't really make that decision.