A few editors are posting things about their slush piles reading. First is Christopher East over at Futurismic on why we reject stories (grokked from Tobias Buckell who linked to another article that led me to this page). And next we have Keven J. Anderson with his view form the slushpile (grokked from the Brandie Tarvin).
Here's an interesting piece about some societal experimentation on what's popular (Wired Magazine). And a Futurismic article on it for the light version. Seems that popularity is somewhat a product of peer review (although they classify it as "luck" it's more of peer pressure thing). This is why, as a creator/author, when you have something coming out that generating "buzz" is so damn important (besides the necessity of early sales numbers). (grokked from Tobias Buckell - this is the original article he linked to).