* Paula Poundstone, comedian who is a contemporary to Bill Maher. * Arianna Huffington, frequest guest of Bill Maher who describes herself as a reformed right-winger. * Frank Luntz, conservative political consultant, most famous for his attempts to discredit global warming science. Bills guests via satellite: * Richard Engel, NBC's Middle-East correspondent, who has covered the Iraq war since it's beginning. * Christopher Hitchens, author/journalist and out-spoken atheist whose latest books is "God Is Not Great: How Religion Poisons Everything."