For me, *if* I get one it'll be the Xbox One. All the stuff that people didn't like about the initial announcement has now been revoked. You won't need an internet connection to play a game - even the "once a day phone home" is gone. They also got rid of the crap that people were afraid about concerning used games.
The #1 thing I have against the Xbox 1 is the same thing I would have against the PS4 if I had a PS3 - no backwards emulation. All the stuff I've bought is obsolete - no big deal there - but in order to keep using it I have to either move it elsewhere or make more of a rat's nest of cabling.
Microsoft says they want the Xbox 1 to be "Input One" - the thing you get everything through. But they directly contradict that by not having an emulation mode - so either you stop playing your old games or you have another input. And don't give me the crap about "it's a new architecture" - In 7 years, the price of the computing power of the XBox 360 is a tiny fraction of what it was 'back then'. You can practically put it on a chip - which could have done the lion's share of the emulation work (I wrote software for a living for 35 years).
For me, one of the appeals was in that I might be able to REDUCE the number of inputs (and remote clutter) now that the game console would have a Blu-Ray player.
So I'm still on the fence... Not sure WHAT I'll be doing.