As newspapers scramble to find ways to increase online revenue, many are finding that integrating social networking elements makes the sites more attractive to visitors and expands online advertising inventory.

Publishers are finding that social tools make their newspapers' content areas more popular, both increasing traffic and the average amount of time a visitor spends at the site, ClickZ writes. Also, user-generated content greatly increases newspaper site inventory, but at a fraction of the money it would take the paper itself to generate the content.

Also, papers are finding that blogs, message boards and user profiles allow local professionals, sports fans, college students and others to interact, forming online communities that can be valuable targets for local, even national, advertisers.

The Bakersfield Californian, for one, is also adding tags to its content, which can allow for highly focused contextual advertising. Dan Pacheco, senior manager of digital products at the paper, says such relationship-building marketing opportunities "will ultimately be more valuable to local advertisers."