I'll be honest. I will read anyone's posts regardless of their post counts. But like Omni said, I will immediately categorize a person as annoying or not annoying. If I find them excessively annoying, I skip past their posts half of the time. I don't, however, use my ignore list. I always feel like maybe - just maybe - that annoying idiot will turn into someone of worth. They usually don't, but I keep my ignore list clear for the special few that surprise me.
I can't say I enjoy this, though. There have been days where I look at stupid post after stupid post and end up feeling like I've wasted my time.
I would spread the cloths under your feet: but I, being poor, have only my dreams; I have spread my dreams under your feet; tread softly because you tread on my dreams.