I have Xbox 360 and now Xbox 1. I cannot speak for PS3 or PS4 but I see a marked improvement with Xbox 1 vs. 360... have Deadrising 3, Ryse and NBA142K. The video is really quite good and I know it will get better. Initial loads take some time (but you can start playing games half way through loading). I really like the voice commands and having it toggle between TV, Games, Netflix, music, etc... There is no stuttering... everything is quite smooth. Knowing this is just the beginning of the life cycle I'm certain both PS4 and Xbox One will continue to get better. I am a huge Halo fan and look forward to the next release at the end of next year.
I like that either one controller or even voice commands can control all entertainment needs and not having to maintain a holster of all kinds of controllers. Within 1 to 2 more years there will be much more clarity about the "winner" if there is such a thing, but for those whose digital entertainment spans more then just video games I have to give the nod to Xbox 1. Sure I'm spending nearly $200 per year for Xbox Live and Netflix, but for me, in the big scheme of things, that is a small price to pay to have a well rounded entertainment system.