Google announced a new AdSense feature to embed a widget on your pages that looks at the content relevancy of your web page and then shows relevant articles or pages from your web site in the widget box.
The goal is to get people to click onto other stories you've written and generated more pageviews and more ad impressions.
Matched content, is a free content recommendation tool for AdSense publishers that promotes your content to your site visitors. Matched content generates contextually relevant and personalized article recommendations from the pages on your website.
Here is a picture of what it looks like:
Google said on Google+, "This new feature can help you increase your site's page views, ad impressions, and could increase your ad revenue by making it easier for your visitors to find your content."
I personally do not have plans on adding it here, just yet at least.
Forum discussion at Google+.