I dont think he will dominate. I think he will win 1 slam, possibly 2, definitely not 3 again. He might well lose his #1 ranking back to Nadal. Breaking down the slams:
Australian Open- clear favorite here. However something tells me Murray might surprise here.
French Open- on paper it would seem he has a good chance after his wins over Nadal on clay this year. However he has underperformed here his whole career and never made a final, even last year. I also have a feeling Nadal will have made some adjustments to be better able to play Djokovic, which would give him a good chance of beating Djokovic on clay and grass atleast by next year.
Wimbledon- this is really his worst surface. He just won last year since he was playing so incredibly well. I see Nadal as having a good chance of beating him here, and possibly Murray if he can overcome his nerves. Federer has declined on grass so not him. Tsonga or Berdych if they get on a roll perhaps too.
U.S Open- he is the favorite for this one for sure and will probably defend. Federer is probably his biggest threat and will be hungry for what is his best chance at another major. Murray, Tsonga, Berdych, Soderling, Nadal, are all possible challengers too, and outside shots at the title.