He finished higher than such well regarded defenders as Kobe Bryant, Tim Duncan, Brendan Haywood, Shawn Marion, and Shane Battier. http://www.nba.com/2010/news/04/20/howard.defensive.poy/
Man Thabo Sefolosha got 8th. I wonder were Batum would have landed if he was healthy the entire season.
If he continues to do well in the playoffs he'll be on everybody's radar next season for the award. He won't win it, but he'll get some second/third place votes.
Nic will start to get his name in there next year once he's played a full season (not counting his rookie year, of course).