He's doing a good job this season, but I don't think he's a lock for GM of the Year. I've always been hesitant to praise a guy who trades away all the youth and all the depth in a couple of blockbuster deals, while giving his tea a two year window to either win a championship, which is the ultimate goal, or implode and have to start from scratch again.
If the Celtics can get a couple of rings out of all this activity, then Ainge did his job. And he's done a good job of building a contender in practically one offseason, which was made possible by the way he's drafted for a couple of years now. But GM of the Year doesn't come until your team actually comes together and plays well on the court.