[rspeer]

It's certainly the same phenomenon as Wikipedia -- certain users become influential, and some of them use their influence to solidify the way they do things and make the site more like what they want. This often is at odds with what a new user wants because they can't remember being a new user.

SO's many levels of reputation that give you additional abilities, I think, made the whole process happen faster. It got the site ramped up and turned into a reliable resource faster, and it also let people create their fiefdoms of influence where they wall out new users faster.