I think it's because Microsoft are saving their developing man-power towards their next system, to guarantee that they'll have a great launch line-up like they always do, unlike Sony who will inevitebly have a lack of decent games at first (PS3 & Vita). Also, the PS4 apparently doesn't have backwards compatibility and so many PS3 games will be out and still relevant towards the edge of the PS4's release that I really can't see myself going with Sony this time. I'll probably get myself an Xbox 720 (or whatever it ends up being named).
Love the the believing of "rumors" kinda pathetic actually.
Best Boss Battle Ever Xemnas- KH2, Long Live Mega Man Legends 3! PSN: Strife1721