Vesa Toskala has been a breakthrough goalie from my point of view. I had always considered him too inconsistent to play in the NHL but he's proving me wrong. He's stuck behind Nabokov right now but he will become a starter in the NHL at some point in his career if he keeps playing like he has.
Since I get to watch Rangers games, Jussi Markkanen(sp?) has been real good for them. Maybe he isn't the "breakthrough" goalie of the year, that would be Kiiprusoff(sp?) but he should get some recognition.