Ilya Grigorik, of Google's analytics team, has announced the introduction of Social reports.

Based on the decade-old concept of Trackbacks, which Google uses in crawling to track referencing links, Social reports will alllow Google analytics users to build a reliable link graph that will help them track backlink URL's, post titles and more.

"These reports provide another layer of social insight showing which of your content attracts links, and enables you to keep track of conversations across other sites that link to your content." - Ilya Grigorik

Knowing which pages and content are helping drive traffic will certainly help website and blog owners understand what it is Matt Cutts and Google mean by "good content", but it will also help them understand what their audience is linking to and sharing, and the kind of content worth reproducing.