Not so long ago, you could look at your Google Analytics account and easily see the search phrases being used to find your site. Don't confuse these with keywords, which everyone says are dead...even Google (http://googlewebmastercentral.blogspot.com/2009/09/google-does-not-use-keywords-meta-tag.html). Metadata keywords in and of themselves are not really of much value, but using them in your content...well, that is the real "Google juice". Google calls these search phrases "queries", but about two years ago, the most critical ones vanished from Analytics, showing "unavailable". If you were using AdWords, you could see them, so it looked like a heavy-handed approach to marketing Google AdWords. It was really more like a repositioning to Google Webmasters Tools.