NBC's Domenico Montanaro has a good look at the most important media markets in the most important states, as measured by SMG Delta.
These are markets in swing states that George W. Bush won in 2004 and Barack Obama won in 2008.
Wilkes-Barre/Scranton, Charlottesville (which has a parking lot that was turned into a fascinating documentary), Norfolk, Richmond, Raleigh-Durham, Orlando, Tampa, Columbus, Toledo, Grand Rapids, Lansing Marquette, Green Bay, Milwaukee, Wausau, and Des Moines.