I'm almost certain I'll go for the PS4 (when the price will be at 300$ or when there will be enough exclusives to justify my purchase) but Microsoft can still convince me.
They need games (obviously) and exclusives mainly. I know like everyone that a new Halo, a new PGR, a new bunch of Kinect games and a lot of multiplatform games will be on the system (a new CoD, a new Battlefield, a new NFS, a new Fifa/Madden and already announced next gen games) but I need something else to buy the system.
If sequels were my only request then I could just buy the new Xbox or PS4 depending on my brand attachment but exclusives are what are making me decide at the end.
Sony showed interesting things with Knack, The Witness (timed exclusive) but the rest even if it seemed good didn't really make me go "wow this is really awesome material here".
Like I said, I'm more entitled to Sony's 1st party / 2nd party games so I'll just watch with no hype. I've had Xbox and Xbox 360 (two systems) but it was only for a few games that I bought theses systems and I ended selling or giving them pretty rapidly.
Xbox is a strong brand and there is a lot of good games, it wasn't just the type of games I like on the previous systems. Maybe this time things will change
Edit :
* always connected doesn't bother me if I can play without kinect (the always on camera connection would freak me out)
* price must be at 300$ with no games
* I may accept to pay for online if there is a PS+ like thing or something that add more value to the service
* Social gaming, f2p, iap and all these things mustn't be a major part of the service too. Or I must have the choice not to participate without feeling that I will miss things (for example not making achievements or social gaming use to be the key to access free dlc or some part of games)
* giving a lot of media features could make the difference