If your hooked now, your hooked for life!
I was hooked on 5k, 10k, 15k, 25k, 35k,45k,50k and im now on just shy of 52k.
I love achievements, its the best thing since slice bread, yeah I find my self sometimes playing games that I have already milked and 1000g like COD4/COD5/FIFA etc, but every now and then I get an urge to go on an achievement rampage!
I had a PS3, and the trophies just didnt do it for me, just a poor copy cat of the achievements!
(PS, you know where your hooked on Achievements, when you hear the achievement sound randomly, when your no where near a 360!)