Dlberry and tabertruths: I've been running an informational site for more than 12 years (more than that, if you include its previous domain), and I've been affected a great deal by Google's algorithm changes--starting with Panda 1.0 in February, 2011. What's more, I know quite a few other legitimate "content site" owners in my sector who have suffered collateral damage from Panda.
Probably the biggest change that I've noticed in Google's informational results since Panda 1.0 has been a dialing up of "ranking juice" for megasites with millions of pages at the expense of specialist sites. Google's Web is starting to look more like network television and less like a plethora of specialized cable channels, which is what the Web was supposed to be not so many years ago.
If a niche site's pages are nudged down in Google's rankings by an average of only three or four places, that can mean a huge drop in referrals and traffic. I suspect that Google knows this is a problem, and that Author Rank (or the boost for site expertise that Matt Cutts suggested would become part of the algorithm this summer) is an attempt to keep Google's SERPs from forever being taken over by megasites' filler pages and stubs.