Most important factor for me- online
The specs look great, games look great, etc... The only reason I still buy a playstation system and have ps3 is for MLB the show.
Now with that being said the reason for everything else I prefer xbox is how usable there xbox live system is. Can see what all your friends are playing, easy to jump in a chat with them, the list of features that make communication with your friends is so much better then playstations I would pay $300 a year for xbox live.
So really with the ps4 it will all come down to if they fix there online, friends type system to be more user friendly. Will they make it easy to jump in a group of friends and talk to them, make it easy to send messages, etc... That will be a big decider for me. I obviously will still buy it for mlb the show but whether or not it gets my money for other things will be decided by that. And also get a more friendly type of achievement system. Trophies was a very weak attempt at a copy.
Are any details released on these things that matter to me?
If you watch the PS4 conference, you will see Sony is making huge strides in communication and connecting you to your friends. It will have everything Xbox Live has and more, such as watching your friend play a game online and even jumping into his game to take control!
The PS4 seems to be very social oriented and I think if you check out the conference or read some of the articles on this website, you'll see that a lot of the things you are looking for will be part of the PS4.