In an aid to reduce the amount of rubbish that gets posted from brand new users (or long time listeners, first time posters), it could be useful to make them sit a short test (or an "interactive tutorial" might sound better).
This "interactive tutorial" might consist of an initial page presenting a cut-down version of the FAQ, highlighting what makes a good question, and what kind of things they should avoid asking.
The user would then proceed to a number of bad question examples, the user would then be required to select from a list of choices, what is wrong with the example question.
Of course, we wouldn't want to deny membership should anybody "not pass", so instead, whenever a user selects a wrong answer, they are presented with an explanation as to why their selection is wrong, and why the correct answer is a more suitable reason. The user should be forced to read this by using a short 30 second timer (or however long), before they can move on to the next question.
This could be extended to work on a per-action basis. For example, before a user can have privileges for an action (e.g. post question, answer, comment, vote up/down, etc.) they have to sit the "interactive tutorial" related to that action.
This could also be enforce on existing users. I would have no problem sitting a few short tutorials in order to earn my privileges back if it means we improve the content from new users.