crobb305 - 4:20 pm on May 17, 2012 (gmt 0)
Like if keyword matches amazon _-> #1 amazon #2-#9 brands etc.
if amazon is filtered -> prepenguin
None of the pages ranking top 20 in my niche post-penguin has anything to do with amazon and no amazon pages are ranking. Appending -amazon.com (or any other domain) does change the serps, but maybe I'm misunderstanding what you're saying with respect to Amazon and its significance.