I'll know I've "arrived" as a programmer when I can predict that problem I think will be trivial to solve is actually trivial--or one that I dread is an even worse pain in the backside than I think it will be--and be correct at least 75% of the time. (Without it being a self-fulfilling prophesy, of course.)
I suppose it's a metric that applies to any number of crafts. But in my little nook/cranny of the universe, it's something to which I can only aspire at the moment.
