Citing a “tough consumer environment” and in particular a “a weaker book market,” HMV said in a brief trading update for the 18 weeks weeks ending August 30 that same-store sales at the Waterstone’s chain fell 4.3 percent, and declined 1.7 percent after you take out Harry Potter. Total sales at Waterstone’s fell 5.9 percent for the period. The chain launched the Sony Reader yesterday with about 7,000 titles available (they expect to have about 20,000 titles by the end of the year) and has enrolled 1.8 million loyalty card members.Statement