5. Jon Stewart (“The Daily Show”)
He may look like the stodgy anchor of a prime-time newscast, but this salt-and-pepper-haired, quick-tongued, stand-up comic turned talk show host, is changing the way people consume the news. While network programs work tirelessly to export their traditional brand of talking-head-heavy programming to the teen-to-twenty-something demographic, Stewart’s aptitude for reporting the day’s events in satire-quipping fashion, has helped turn the faux broadcaster into a counter-culture hero. Thanks to Stewart’s popularity, more teens get their news from Comedy Central than CNN. Who said the news can’t be fun?

4. Oprah Winfrey (“Oprah”)
By 1986, Winfrey’s mid-afternoon talk show had become the most watched in television history. Now, with a successful magazine, book club and acting career under her belt, Winfrey is worth more than a billion dollars. What do you do as one of the world’s wealthiest people? Spend, spend, spend. Winfrey’s dropped more than $50 million financing philanthropic construction projects in Africa’s poorest regions, and dedicated millions more to help build programs aimed at educating poverty-stricken teens in her own backyard. And who could forget Winfrey’s legendary car giveaway? The big-hearted host gave needy audience members new automobiles during a TV taping in 2004 — all 276 of them.

3. Conan O’Brien (“Late Night”)
Famous for his witty, often self-deprecating humor, the fiery, redheaded late, late night talk show host has solidified his legacy as one of television’s most likeable funny men. Equipped with a mix of wry, clever and sometimes risqué comedy, O’Brien has secured a contract to take over as the new “Tonight Show” ringmaster when Jay Leno retires a few years down the road. Nightly lineups include celebrities, athletes, musicians and an odd mix of pop culture icons (Mr. T, Chuck Norris and Abe Vigoda appear in recurring segments). And who could forget the hilariously inappropriate “Triumph the Insult Comic Dog,” “Pimpbot 5000” or “Masturbating Bear”? O’Brien has successfully turned the poop joke into an art form.

2. Howard Stern (“The Howard Stern Show”)
From radio to television to satellite, he’s maintained one principle: Stern does what Stern wants. In 2006, after years of butting heads with the FCC over his bawdy on-air persona (Stern’s paid out a career $2.5 million in decency fines), the shock jock gave the government the metaphorical middle finger, trading his slot on the public airwaves for the promise of freeform, uncensored Sirius Satellite Radio. Millions of listeners subscribed, shelling out large wads of cash just to hear the foul-mouthed host chat with a rotating list of oddball guests. Now that’s personality appeal.

1. Johnny Carson (“The Tonight Show”)
“Here’s Johnny.” Carson’s famous tag line, piped out each night by sidekick Ed McMahon, may go into the annals of TV history, but it’s the late-night jokester’s penchant for whacky sketches, parodies and gut-busting monologues that helped leave his immortal imprint on the genre. Carson wrangled celebrity guests, musical acts and unruly animals for NBC’s flagship after-hours program for nearly three decades — the longest talk show tenure in television history — before turning over the reins to Jay Leno in 1992. His secret? With Carson, you always knew what to expect — good, wholesome, heartland humor.

I love Howard Stern, but I wouldn't put him on the list. Instead, I would put David Letterman. I agree with the rest of the list.

Even though I'm not a big Carson fan, I think there's no denying his contribution to late night television and I definitely thinks he deserves the #1 spot. I did watch The Tonight Show a little bit towards the end of his run, only in the Summer though as I was in like third grade (maybe fourth) at the time.

This is one of the few times I agree (for the most part) with one of these MSNBC lists.

I would have like to see more Daytime hosts on the list.