There are two main story lines for the Pistons tonight as they end their third straight season without a postseason appearance -- one dealing with the immediate future and one concerning the future of the franchise. Will it be the final game of center Ben Wallace's career? After saying earlier that his 16th season would be his last, he has hedged his bets lately. "Who knows?" he told the Free Press recently. "Everything's open." The Pistons haven't revealed any plans to note the occasion, although something might be done in case tonight is Wallace's final time competing on the Palace floor. The team had a voluntary workout Wednesday, and there was no word from Pistons coach Lawrence Frank on whether he'd start Wallace. Frank also started conducting season-ending exit interviews Wednesday.