After being to the Eurogamer Expo it was really disappointing not having the PC version on show.
Why?
If so then they'd need PCs, keyboards, and mouses on hand. Do the math. They can hook a 360 controller up but looking at the whole picture more trouble than it's worth. So they went with the 360. Might aswell ask why no PS3 version?
As a PC player I'll skip over supremacy comments as to me it doesn't matter. Bethesda already was one of the most mainstream RPG devs by Morrowinds time. Consoles have little to do with how Skyrim is progressing other than graphical features and DLC.
Audiences do. Which is(Not casual) but multi-genre and a vast majority of core RPG players who've never touched a real RPG with a rule-set let alone tabletop. The core RPG audience now isn't the same as the 80s or 90s. Take what we can get.
Deus Ex was barely an RPG in the first place, Deus Ex Hhuman Rev from recently is even less but does tons of things better than both RPGs and action games in the last decade.