If you've ever seen Oblivion runing at 1920*1080 with a full set of 4096*4096 hi-res textures with 200+ plus mods added, you'll know why you shouldn't touch Skyrim with a console
As Bethesda have said they will include hi-res textures in the PC version it should look graphically superior from the off on a PC even before the modding community completely re-write the game! You'll need a Phenom X2 quad core or better, an ATI 4870 or better, and at least 4gig of DDR3 Ram. Hope this is useful.....
Yeah, the end result would be better, but getting that slick computer set up takes time and a lot of money and technical know-how (if you are building the computer yourself), not to mention the amount of time it takes set up those 200+ mods and texture packs.
I am getting Skyrim first on the 360, because I am first and foremost a 360 user, it just feels more natural to me than a keyboard. After I get bored of Skyrim, which will take a while, I'll buy it on the PC and mod it to my liking.
And you don't need a super computer to enjoy modded TES, there are a lot of excellent small mods that completely change the way the game is played, while still being FPS-friendly.