Does this mean its not in Google’s Index?  I’d say not necessarily.  A little digging around and I found a leading .edu site which not only ranks top for a unique phrase but also doesn’t show up in Google’s cache.  My conclusion? Google is being even more anti-SEO and doesn’t want to show SEOs anything a bit like the link: search commands and the more accurate site: search commands unless you’re the website owner and therefore can access the webmaster central account.