Zach Galifianakis, Jonah Hill Make This Week's 'Late Night Lineup' Extra Funny

We're only a week out from Conan O'Brien's game-changing debut on "Conan," which will open up next Monday (Noevember 8th) with Seth Rogen, Jack White and a mystery poll winner (at the moment, it seriously looks like Jack Nicholson, who hasn't done a talk show in over two decades) taking up couch space on that first show. In the meantime, you can catch a dry run of the series tonight (Monday, November 1) at the show's official Web site starting at 11 p.m. Eastern. They'll run through "Show Zero" with most of the pieces in place (including a better part of the band), so it should give a reasonable indication of what the show will actually look like when it storms onto cable next week. (Be sure to stay tuned to the MTV Newsroom Blog for Conan-related updates between now and then.)

In the meantime, the show must go on for the hosts currently on the air. "The Late Show With David Letterman" welcomes some heavy hitters this week, including Robert Downey, Jr. (Monday), Tina Fey (Wednesday, November 3), Steve Martin (Thursday, November 4) and Tracy Morgan (Friday, November 5). Over on "The Tonight Show," Jay Leno will talk to the likes of Janet Jackson (Monday), James Franco (Wednesday) and Jennifer Grey (Friday). (It should be noted that both "The Late Show" and "The Tonight Show" will be pre-empted on Tuesday, November 2 in favor of manic, borderline irresponsible election coverage.)

ABC apparently doesn't care as much about the election, as "Jimmy Kimmel Live" is scheduled to go on as planned on Tuesday night with a show featuring the latest "Dancing With the Stars" castoff as well as actress Thandie Newton. Kimmel will also welcome Will Ferrel and Good Charlotte (Monday) as well as "Eastbound & Down" star Danny McBride (Wednesday). "Late Night With Jimmy Fallon" features Jonah Hill (Monday), Zach Galifianakis (Wednesday) and a great Friday night tag-team of Lewis Black and Elvis Costello.

Across cable, you should tune in to see Eddie Izzard on "Chelsea Lately" on Monday, watch Mariah Carey on "Lopez Tonight" on Wednesday and catch presidential historian Doris Kearns Goodwin on "The Colbert Report" on Wednesday (because sometimes you need a bit of education before drifting off to sleepland). And it's really, really good to have Ellen DeGeneres back, as her show features Taylor Swift (Monday), Mariah Carey (Tuesday) and James Franco (Friday), and that's just this week.