He's an energy player with a skillset we could use if he can bring it consistently. Those types are good to have around, especially on a playoff team, because they fire up both their teammates and the crowd. Inexperienced as he may be, he's showing progression on both ends. Remember the Boston game?
First of all, he didn't look or act scared at all, even in the guts of the game (it's been a recurring theme anytime he plays - he's respectful but clearly a force to be reckoned with). Big plus. It's nice knowing the rookie won't be easily intimidated.
Second, he was a big part of that +23 rebounding margin, and played just about as spectacular as you could have wanted on both ends, including guarding multiple bigger, more talented (supposedly) Celtics with success and scoring against those same guys.
He's had some nice blocks and other defensive plays this season. And wouldn't you describe his time now as "limited"? He only averages 15MPG, yet posts some of the League's best rebounding stats per minute.