I don't have any of the next gen consoles yet, but I've had my fair share of consoles up through the years (Xbox360, PS3 and Wii amongst them), and each console has its own ups and downs. For instance, I use my PS3 for watching Blue Rays and DVDs only these days. Heck, I only ever acquired 2 games for it since I bought it way late (early 2013). The Wii I have for Offline multiplayer games which in my opinion, beats any of the other consoles in that compartment (Mario Kart, Smash Bros, etc). And no, I'm not talking 2 player Coop, I'm talking 4 players on 1 screen. Plus I have to have Zelda, easy as that.
For online multiplayer and competitive gaming, Xbox360 was always my best bet. Dunno how many hours I played Halo 3 back in the days for instance, neither Left4Dead 1 and 2. So yeah, ended up buying all 3 of them (Got Wii and 360 in 2007 I believe, 5 years before I bothered getting PS3). Also had Xbox, Nintendo GC and PS2 (temporarily), but since xbox, I've been more of a Xbox/Nintendo gamer, while I was a Nintendo/Playstation (with N64 and PS1) gamer before that.
Point of all this is to sum up towards the next gen, which I intend on getting this year. All I know is that I ain't going to buy all 3 again, and I have to have Wii U if only for the new Zelda game. But I need either XboxOne or PS4 for obvious reasons (more games I enjoy playing, better online, etc). So which one will I get? It all boils down to controller for me... For someone who had PS1, 2 and 3, I never particularly liked the PS controller. In fact, I liked it the least amongst all consoles I've had from all 3 of the publishers (Nintendo, Sony, Microsoft).
What don't I like about it? Is it too small? No... Not really. What I don't like is the position of the analog stick. For me, that ruins competitive gaming like Fifa and such. I can still play Fifa with my friends on the PS4 (with which controller has improved a bit but not quite), but I'm ten times better on the Xbox. I just can't get the same things done on the PS Controller so to speak. The thumb tires out and it slips off the analog stick all the time which is a bother. The only game I can think of that feels the other way around is Tekken. I bought Tekken 6 for xbox360 and I didn't like the control schematics much due to being used with the PS controller with those games. But that is the only exception for me at least.
So yeah, for me, it comes down to controller basically. Plus the fact that I can't own all 3 consoles for the 3rd time in a row anymore, it's not really worth it. Plus the obvious fact that I ain't going to abandon my Gamerscore which is that. Trophies I never really cared for even though I collected some. And to top it, XboxOne also have Blue Ray now which renders a 3rd console pointless. Sure I will have to let go of some beloved series, but I guess that's just how it has to be.
With all that said, I will be getting Xbox One and Wii U and skip the PS 4 (the first PS console I'll skip in fact). For me personally, PS's been all about being a Brand rather than a gaming company since PS2. From my experience, people buy PS because they know of it and its exclusives, much like people buy Nintendo because of Zelda and Mario. Xbox has been getting there too slowly, but it ain't going to catch up with Sony and Nintendo over in Asia, that is for sure.