I'm not very sure about that. Amazon's site may not be beautifully designed but it works. As they advertise, it has never taken me more than a click to buy an item unless I want to change something. Also, it has one of the better product search engines amongst all retailers. Their reviews are generally considered genuine and useful and they're clearly laid out. I'm generally happy with their website design.
Notice that you can have great reviews or product search engines despite a busy chaotic layout - the search engine source code doesn't give a toss what the pages look like as long as it has the data it needs, and the reviews come in if you have enough customers and don't make too hard on them to submit.
