Why do Amazon.com pages tend to rank well for product queries?

Matt's answer:

MATT CUTTS: Today’s question comes from Steve K in Pennsylvania. Search for a physical product usually ranks Amazon number one, even though it may not provide the best user experience. What is being done to prevent large corporations from dominating search engine results? It’s an interesting question. Because I think, in general, not to call anybody out, but I think Amazon does have a relatively good user experience in general. I wouldn’t necessarily agree that Amazon always ranks number one for every physical product. So typically, when I do a search for a book, Amazon is up there. But if there’s an official homepage for a book, it often ranks very well and sometimes number one as well. The interesting thing is not every book has a homepage. This is something that still surprises me. You’ll have a very savvy author, they’ll have a web page, but they might not have a landing page, or a page dedicated to that specific book. Sometimes it’s just a lack of savviness. But I was looking at a dictionary, Mrs. Byrne’s Dictionary of Unsual, Obscure, and Preposterous Words and really there was no content about it on the web other than say Amazon or Goodreads, or there was something with Google eBooks. So the best answer is make sure that there is an actual page for your product. In general, Google does try to figure out what are the official homepages. Whether it be for governments, or universities, or states, or whatever. And we try to make sure that we do return those when possible. So we are mindful of whenever users do a search and then if they complain to us. If they’re complaining that they’re not finding the official homepage for product, then that’s something that we do take into consideration. But in general, we do look at the number of links, we look at the content of the page, and if one particular website is able to get a lot of links because a lot of people think that it’s a great site, then in general, usually it should rank relatively well. And I don’t think that that by itself is necessarily a problem.

by Matt Cutts - Google's Head of Search Quality Team

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