What portion of your website traffic begins when a user follows the results of a search on Google, Bing, Yahoo, etc? Keep in mind you need to ensure your content strategy includes matching search results with landing pages. It isn't nice (or a good example of usability) to provide links that don't lead to where the user expects them to lead. Take the following example of how Edmunds has failed in this respect.
Search on "safest cars" and you'll see these results.
What do you expect when you click on the Edmunds link? A list of the safest cars? What you get is the following.
Do some searches on your organization's content topics and see if the search results and landing pages match up.