Different Anonymous here

I would say its partly due to introduction of stackoverflow with its broader focus and better voting system -- its like a superstore , one stop shopping all the way :) even with its lower volume of perl questions, its still got merlyn / ikegami / Corion ... posting regularly . For some things, no matter where you go, its the same persons answering the question, esp perl, but stackoverflow has cpan authors as members that were never perlmonks