It may depend - I recently brought 6 total stinkers in and got the Extra $10 for 2 promotion but one of my fraternity brothers works at EB so sometimes I think I get a little help with trade-ins. But I'm inclined to say as long as its not sports, it's probably good even if it's POX.
EDIT: I know for a fact Devil May Cry 2 will work, its on of the ones I traded in - worth $3 before bonus