Over a sustained 2.5 year period, not really. I mean what percentile of activity/reputation do you think you'd be in for all members in that period? I'd guess well over 50... perhaps 75 or 80?
Programming is my full time job and I ask questions on SO somewhat regularly when I get stumped, and occasionally peruse for questions I can answer, but I don't make any efforts in particular to raise my rep for its own sake, and I just reached 100 rep after being a member for a year. I feel like I fit into the 'casual user' camp that he's referring to in the OP since I'm still pretty limited in my participation even though I FEEL like a somewhat invested member of the community. But I don't think these issues would really apply to you at your level of activity (and kudos to you for that, btw :) ).
Programming is my full time job and I ask questions on SO somewhat regularly when I get stumped, and occasionally peruse for questions I can answer, but I don't make any efforts in particular to raise my rep for its own sake, and I just reached 100 rep after being a member for a year. I feel like I fit into the 'casual user' camp that he's referring to in the OP since I'm still pretty limited in my participation even though I FEEL like a somewhat invested member of the community. But I don't think these issues would really apply to you at your level of activity (and kudos to you for that, btw :) ).