The Clifford Berryman exhibit that is opening later this week at the National Archives continues to generate press. You can see my post about the exhibit here.
And the previously mentioned article in the Washington Post:
"Caricaturing Campaigns: Exhibit of Cartoonist's Sketches Links Politics Then and Now," by Michael E. Ruane, Washington Post Sunday, February 3, 2008; C03.
and this one that snuck by me until today, "National Archives unveils political cartoons," By Johanna Neuman, Los Angeles Times Staff Writer, January 31, 2008.
Jennifer Rios of the Scripps Howard Foundation Wire wrote one too "After 60 years, political cartoons in exhibit remain relevant," - you can register for free to view it, or see it here.