Like i said, fedor is really the new style right now, because all the others are already incorporated in the "new" generations of fighters(gsp is a good north american example, if not the only).
But apart from him, and frankly i dont think sambo can bring that much more to the game, i think mma developpement has a reach a plateau. BJJ is starting to be less effective(less and less submissions happen when top fighters collide, same for reversals). For example, barnett vs nogueira trully shows how ground game are being cancelled when both fighters are incredibly good at it.. right now its fair to say nog is the best(or at least top 3) bjj fighter and barnett is very skilled at wrestling(is there even a difference now..), and the fight was mainly decided on who beat who standing up(and nog clearly kicked barnett's ass).
the main thing fedor has brought new to the game is his ability to combine striking, positions and sub defense(and offense i guess) to his ground fighting. Before that, most ground and pound were horrible at defending submissions.
But how can it evolve more?