I've been having an interesting time lately engaging with the StackOverflow community at https://stackoverflow.com/.
I got involved because I had found lots of useful code on there when rewriting notamos.co.uk, and thought I should try to give something back.
It's been a mixed experience, mainly because I expected it to work like Microsoft Community, an environment with which I am very familiar from past Windows Phone forum involvement; wrong, because StackOverflow is explicitly aimed at building a knowledge base rather than at helping people work through problems. On StackOverflow you are supposed to ask an intelligent question, get an intelligent answer, and move on, with discussion/teaching discouraged (though by no means absent in practice).
The most assumption-challenging question I have encountered is (almost literally) 'I have written a complex Java-based web application, I want to put it live, what server should I put it on?'. But, far worse, so many developers appear never to have been taught exception handling, problem determination, basic relational database design, web application security, or even how to articulate a problem clearly. No wonder (to reiterate a regular rant) there is so much bad production software out there.