After the standard "this is awesome" (which I do believe), I've gotta say: this really sucks for traditional retailers. Amazon can always offer lower prices because they don't have to maintain storefronts.
But this has always been the case, even before this feature; you go to your local TV/furniture/etc. store, look through the products and make your decision, and then go home and buy it off the internet for cheaper. What'll ultimately happen to "normal" stores?