A Class D airport isn’t too bad for flying into non towered (many D airports are non towered at least part of the time). I wouldn’t want to fly into a Class B or even C no tower.
I don’t believe there are any Class B or C airports on the list of possible tower closures:
http://www.usatoday.com/story/travel/flights/2013/02/22/travel-delays/1938959/