Rehashing the post from Should we target Social Media?Should we target Social Media? and the frantic two days I spent searching feeds, creating a system to help extrapolate Ubuntu questions and pair with answers might still be useful - as well as posting statistics like: Popular questions as they arise, etc.
It really shouldn't be too much a HARD SELL for the site, but rather an interaction with the other Ubuntu users - and prospective Ubuntu users - on twitter.