If poll/fun/discussion questions are so critical to avoid on SE sites, why isn't there a big slogan pasted on the page header:
The place for specific, technical questions about programming.
Users may not read the FAQ, but I generally feel a big stamp on the logo is harder to avoid. Not all user issues have to do with documentation; a lot of it has to do with site branding.
On first glance, stackexchange sites look like any other Q and A site. They work much better than that, but in the wide world of the internet, the distinguishing focus of these sites should be readily apparent to a new user on first glance.
In a recent comment Jeff made the point that its okay to "slap a few wrists" to avoid yahooanswerfail.com (amazing site btw). But why slap wrists if you can avoid it? The other comment was that it's better to have 100 of the 'right' users than 1000 of the wrong ones. In teaching, we call this the fallacy of the gifted student. It's true that some people are predisposed to success, experienced, polite, preternaturally forum-ready, but the vast majority of people just don't know what's going on. I think the best way to get them on the same page is to make it very visible what the site is about and then to continually direct people to good resources that explain it.
The internet is full of crap, and people with contrary intentions, but there's still room for turning those "1000 users" into "good users" with a little documentation, good user interface design, clear moderation (with explanations), and some friendly guidance.
This is going to be more and more important as SE expands outside of its niche of relatively hard-core coders and computer users. The rest of the world is less inclined to intuitively understand the focus which these sites are based on. There might be enough SOFU users to 'seed' the hundreds of area51 betas, but eventually they're going to have to fly on their own and fend off hordes of average folk who just have a query. Make it easy for them.
note: This is not about better notification for the FAQ. I literally mean, add the words: "The place for specific, technical questions and answers about [cooking]", to the main page, header logo on every StackExchange site. FAQs are another issue. This is about clear, up front branding--communicating directly with the user in a way that doesn't require them to 'read' or think. To make the unique focus of the site immediately, explicitly apparent.
Mockups (MS Paint)