Playing on a X-Box, some of my friends on a PS4. PS4 has some good game (Last of Us, Killzone) but the Xbox doesn't do only game. It's a multimedia center. I can play games, watch a blu ray, watch a DVD, listen to a CD (the PS4 can't, i think) rent a movie , twitch, twitter, watch the UFC , i have EA access. I can play witcher, then listen to a radio and after relaunch Witcher without loading time at the same place that i have stopped, more and more. the PS4 do a lot a thing i've said, but not so good. With the retrocompability, i will play some game of my 360 (Skyrim, Mass Effect, Red Dead) and soon, the mouse will be compatible with the One. It's a real multimedia center.
But the PS4 still have very good game that I'd like to see on the One. The last of Us, Horizon New Dawn, etc.. so the PS4 is a Gaming console