Guests: Fmr Sen Mike Gravel (Alaska), diplomat Barbara Bodine, musician John Mellencamp; via satellite, entertainer Harry Shearer and PETA president Ingrid Newkirk

Topics: Hurricane Katrina anniversary, Larry Craig arrest and resignation, Alberto Gonzales resignation, environmentalism and energy needs

Guests: Columnist Christopher Hitchens, author Shashi Tharoor, comedian Harry Shearer, author/sex columnist Dan Savage (election correspondent); via satellite, Gov Ed Rendell (PA)

Topics: Pennsylvania primary, Al-Qaeda in Iraq, appeal of Barack Obama, religion in politics

Guests: Counter-terrorism expert Richard A. Clarke, author Andrew Ross Sorkin, columnist Reihan Salam, MSNBC analyst Michelle Bernard, actor Harry Shearer

Topics: Osama Bin Laden's life in the compound, Pakistan as ally, Newt Gingrich, job gains/losses in the private and public sectors, US Army Corps of Engineers, FEMA, education, green energy, John Ensign scandal, pediatricians and gun safety