The Project for Excellence in Journalism has started to chronicle the coverage of bloggers and the mainstream media --- I suspect it's in order to determine the differences.
The second edition finds quite the variance. The mainstream focused on the economy, while the blogosphere had three principal stories --- the economy, President Obama's criticism of Rush Limbaugh, and a road sign that had been redone to suggest a zombie attack was coming.
The New Media Index promises to be a highlight of media assessment.