PS4, based on me being stereotypical and determining what kind of gamer you are :D.
It's really hard to say, unless price is no factor, then it comes down to how bad do you want certain PS4 exclusives. Or PC exclusives or games that are severly gimped otherwise.
Do you prefer mods (gameplay or graphics wise), Emulating old games (you can play pretty much any pre-wii game on PC though you need to tweak a lot. higher image quality (AA, Higher Resolutions>Greater than 1080p, 3D gaming, 120 HZ or some variety).
That said, I agree with JoeTheBro, that I'd wait to invest on PC rig. Things that are good bang for you but now could possibly have issues with console ports from next gen. If you're going absolutely bleeding edge then I think you'd be fine, but that would mean cost isn't a factor for you and it is. I'm waiting on both, because launch consoles sometimes have issues, and no games I'm interseted in.
