I played a game with someone and lost the second (maybe also the first) point because my player basically wouldn't move, although the ball continued fluidly (ManuTOO said this should not happen; see this post for a history of this: http://www.managames.com/Forum/viewtopic.php?f=8&t=2709&p=31906
Somehow I managed to win the match, but I had to make many adjustments. I tried to watch the replay of the saved match (not to look for lag, but just to enjoy it), but only the first game will play correctly. However, finally, the replay does show somewhat the issue that I've reported. You can see this at the end of the second point of the first game (after this point, the score becomes 0-30) in game 1. If you will replay that point and set the playback to 1/4 speed, you will notice that the winning return comes toward my player fluidly, but my player stops very short of the ball. Also, and most importantly, you will notice that when my player swings (viewing at 1/4 speed), the swing is very jerky, whereas the movement of the ball and the sideways movement of my opponent is continuous and fluid. If you view other strikes at this same speed that weren't affected by lag, they will be fluid. So, there it is. The ball and my opponent move normally, and I move as if I've been zapped with a slow-motion ray or something. Maybe because of the lag, the replay won't play correctly after the first game, but the first game is correct.
Edit: You can also see the lag effect at the end of the first point of the match. At 1/4 speed playback, you will notice how the swing of my opponent on the winning return is quite fast, even at 1/4 speed (best seen with my opponent at near end, my player at far end of court). The ball movement is also fluid, but my swing is jerky, and my player doesn't get close enough to the ball to hit it.