This video is a good illustration of the gems you can pick up if you follow the right folks on Twitter. I stole borrowed this from a tweet by the Washington Post book reviewer Ron Charles. He makes pretty damn funny video book reviews himself (if you like the one on Franzen's Freedom, search YouTube for "totally hip" and "book review" for more).

But the reason I love this video is it manages to simultaneously show you how to promote your book and how not to promote your book! And of course, it is hilarious, too.