Sony has been doing alright lately....and a further upswing is probably certain, that is until a year or so after the PS4 comes out and Sony shifts basically all of its resources to the PS4.
In terms of things that could totally wreck the PS3s progress they would have to be pretty big, things like
-No PS3slim or price cut
-360 coming out w/ a slim model and substantiail price cut
-360 caputuring exclusive deals w/ some PS3 franchises
etc