Well, I've played both the 360 and PC demos, and I can safely say this. Both are awesome, but the PC version is more like a more fast-paced version of Origins, while the console version is just completely different, and just a lot more action-based. Even on medium settings (why can't we set it to high, dammit?!) it looked fantastic on my rather modest machine, but I honestly just preferred the control setup (and the ability to play from my couch and on a big-screen TV...) that the console version offered. I'll be getting it on 360 first, then maybe the ultimate edition on PC when it comes out.
Oh, and I saw the ps3 version today at a friends house, no noticeable difference between that and the 360 one.