He had a disappointing first half of the season, got moved to Johansen's and Arvidsson's line, went on a tear in the 2nd half (completely making up for all of the lost production the first half), and went back to disappointing when Johansen was injured. He seems to really need that strong center to carry the puck and dish it to him or else he tries to do everything on his own.
Perhaps the best anecdotal evidence of that is the moment in Game 4 when he received the puck from Jarnkrok (I think that it was) in the slot and tried to pass it back, even though he was one-on-one with the goaltender. I suspect that he would've shot it if he had received the pass from Johansen. Without him, though, Forsberg is clearly the best player on his line and seems to play more like a playmaker, trying to set up his inferior linemates, instead of letting them get the puck to him for his snipes. He needs to not overreact and put some faith in his linemates to get him the puck so that he concentrate on his usual game that he has success with.