Wow! Thanks for the info! That helps a lot. And I would classify me as a -1.0 player! Until I really pick up the racket, I can't be a 1.0!
Actually Dallas what OSU said is wrong. The numbers represent the average number of shots per rally you "can" hold in a match. A 1.0 player will make only one shot, and a 5.0 player will make about 5 shots.
Another way of looking at it is, its the number of OMG shots one can make in a given game (on average). A 5.0 player can pull of 5 OMG shots - maybe an ace, a superb volley, forehand or something like that. A 1.0 player can get the serve over the net and goes Oh my God! and collapses, if a 1.0 player can resist collapsing he can become a 2.0 and beyond.