Thanks for the input Dechristo and Ketch. Let me give you a little more info about myself.
When I started rock climbing/bouldering, I could not even come close to touching my toes (with straight legs), and I was similarly inflexible in other stretches. I started stretching daily (more or less), and within a few months I did get more flexible. I could touch my toes, and even get a couple knuckles on the floor if I was particularly warm. The forward bend is really the only stretch that I have used to monitor any progress, but I think my hip turnout increased slightly as well. My flexibility then plateaued and I have been about the same for about 4 years. I still consider myself to be fairly inflexible, and I feel that it is a real weakness in my climbing (especially on near vertical walls, like a lot of climbs at Smith). I have tried some yoga, about 1 or 2 times per week, in addition to 10 or 15 minutes after I climb, or after a run. I didn't see any results from yoga after a couple months, but maybe I am not doing it often enough, or maybe I need to do it for a full year to see increased results. I also know there are a lot of other theories about the type of stretching needed to get more flexible (active isolated stretching, PNF stretching ...).
I am looking for what worked for others to really get more flexible. Is it possible that one day I might be able to do the splits? Could I one day step up to a hold at nipple height? Or am I doomed to complaining about gym routes that were set by short, flexible routesetters?