Since there has been a lot of discussion regarding the scope of the site in the past, I think it is time to push out something concrete and organize what has been presented thus far. Based on what Nick proposed, I've fleshed out something a little more thorough.
Note: Some of these linked meta posts are for reference. Not all of them have to exist in the FAQ, but some might be useful.
Edit: I've proposed the FAQ as a community wiki answer. Please feel free to update it and add/remove content as necessary. The first proposed version will live in this question revision. I want to give this about a week before pushing it out.
Update: Since it has been about a week, I'm going to be pushing this out to the actual faq. There haven't been too many updates or feedback, but the ones made have been helpful. Any future amendments to the faq should be raised in a new meta post.