With that said, I think we should be careful of where our collective conscious takes us.
There are certain attempts to fix the knowledge gap issue, namely Q&A sites, as well as places where people can share their knowledge. But Q&A doesn't seem to work for most things beyond the basics: there isn't an objective answer, as everything is a trade off, and questions aren't as good as a conversation would be for context and everything else. Even for Quora, where the questions and answers can be subjective, there is an implicit requirement that both of them have to be self-contained (otherwise, it just doesn't make sense). It's evident to see in the "naive" question on Quora: sometimes you can tell the asker knows a bit and wanted to ask for more, but the resulting questions just come out very awkward.
And finally, I think that people are more reluctant to just share their knowledge (directed at no one), for a variety of reasons: it's actually hard to just write about things - there are a big gap between knowing something, and being able to write it down clearly, we mostly can't write a book, but everyone of you will have a thing or two to teach me regardless. It might seem wasteful (who would read this?), or it's just simply never come to our mind that's the knowledge is valuable - familiarity makes everything seems trivial. Most of those issues would not exists in a small group settings.
For a more concrete idea, think of a small but active mailing list, IRC channel, or subreddit, that's approximately the desirable result. If you can, make those mainstream, pretty please :-).
I've actually been working on a side project for a couple of weeks - it's a chatroom-based community. I think it'd be nice to have a place where people could go and talk about specific topics, without having it be all about "content", and without the judgmental weed-out process that karma-based sites force on users. Kind of like a live version of Reddit, you know? As useful as IRC is, I don't think it will ever become mainstream.
Anyways, here it is - let me know what you think! http://www.toka.io/
*You'll need to sign-up to use it.
One-on-One connectivity with a (self proclaimed?) subject matter expert, where the subject could be anything.
Things like Reddit and Quora exist, and Ask HN, how to wikis, guide web pages, etc. etc. but one issue I have with the forum style is that it doesn't foster a student-teacher / master-apprentice experience because there's always someone saying "no, that's wrong" -- or something to that affect.
Connecting students with teachers, where 'student' means someone wanting to learn and 'teacher' means someone willing to share experience and knowledge.
Does such an app exist?