I have preorders on both of these things and am still unsure what I'll do. The PS4 is cheaper and seems like it will be the better system in the long run but for exclusive non-PC games that interest me, the Xbone lineup is way more appealing. I'm super into Dead Rising, so DR3 is in, and I've liked Forza in the past so if that's not a clusterfuck I'd probably be into that too. I'm even considering Ryse after seeing the graphics in that story trailer that just came out.
PS4 has Killzone, but I've never bothered buying a Killzone though I've tried a few demos. If I get one, I'll pick it up though as it does look kinda pretty, and it's not like I'm going to buy Knack to break the system in with

Resogun looks great but it's not a system seller to me from what I can tell.
I have a decent PC so 3rd party stuff might not do any better on these things anyway.
I could use a quieter/nicer blu-ray player and media streamer so that's something these consoles have going for them...
Edit: I forgot about Killer Insinct and Crimson Dragon. Both look like possible buys to me too.