As I see it the information they provide on keywords in their SEO guide is wrong. If I do a search here in the UK for the word "computer" then Dell is listed in the top five. The word computer does not appear anywhere on their homepage. How can a page be listed for a keyword that does not appear on that page unless there is a bias towards big brands?
(Added: I do appreciate the effect of inbound links in this case but surely the word should appear on the page too?)