Andy Roddick changed the weight distribution of his racquet a month ago to make his racquet more spin friendly. The giveaway? His 2hb is not nearly is flat and powerful as before, even though his stroke is the same as before. This indicates that he has moved more of his counterweight from the upper handle to the butt, thereby making his racquet more polarized. It effects the 2-hander more than his other shots, but it also adds a little spin to his forehand and serve, making them less penetrating, but heavier with more margin for error. He now has the option of hitting a cross-court backhand pass if needed. If you don't believe me, watch a tape of Roddick during any match from Wimbledon or earlier, and you'll see that the ball comes off his 2hb differently. You'll also notice that his serve is not as flat.