While I am not the Elite Score Whore that Matt is (he has the badge to prove this) I have passed 15,000, and actually made it to 16,000 without breaking a sweat, thanks to Guitar Hero III, Rock Band, The Simpsons Game, and to a lesser extent PGR 4.
I would say 16,000 Gamerscore in a matter of two years is pretty good. I don't have the 52,000 Gamerscore that Matt does, but I don't play as much (or as many games).
According to my Xbox 360 blog, I only play 56.6% of my games (97.3% for Matt). That is probably pretty close. I have had my 360voice account for over a year now, so the data it tracks is pretty accurate.
