The Detroit Pistons were mathematically eliminated from playoff consideration on April 8th with a loss to the Boston Celtics, although they were realistically eliminated a number of games prior to that.
As I have noted earlier, the race for the 8th seed is likely to come down to Boston Celtics, Indiana Pacers, Charlotte Hornets and the Detroit Pistons, while the Orlando Magic could potentially make it a five team race for the final spot in the playoffs out of the East.
I believe each of the teams listed above has improved this offseason so it is likely the team that gets the 8th spot in the East will need to win at least 40 games, the last time the Pistons achieved such a feat was during the 2007/08 season.