This isn't really surprising, though - and it doesn't even look all that bad either, though it would obviously be better if bloggers would cite a wider variety of sources in general, to prevent the whole "informational monoculture" problem from getting out of control.
Thing is, if you look at the list of most-cited WP articles, most of them are for new, net-centric subjects - words like "meme," phrases like "net neutrality," and of course, "Snakes on a Plane." Those are also things that would be of interest to the typical blogger, whereas classic literature or zoology or Chinese architecture generally wouldn't be. So while it's certainly disappointing, I don't think it's anything to worry about - IMO we should still be more concerned with what goes on within academia, the non-fiction book world, and traditional journalism.
Hmm,
sounded good at the time, anyway...