Craig Ferguson, Jimmy Fallon, Jimmy Kimmel Craig Ferguson, Jimmy Fallon, Jimmy Kimmel

Can Jimmy Fallon survive his Late Night competition? With Conan O'Brien departing for the Tonight Show, fans of O'Brien's occasional sharp edges might depart for Jimmy Kimmel Live — but those who tuned in for O'Brien's heart might find a better soul mate in Craig Ferguson of the Late Late Show.

Fallon brings youth and energy to the Late Night desk, but no one knows what else. Looking ahead to his debut Monday, check out the hosts' strengths, weaknesses, and occasional tendencies to overshare.

Jimmy Kimmel

Show and Time: Jimmy Kimmel Live, ABC, 12:05 am

Years on Air: Jan. 2003-present

Trademark: Comedian's-comedian style surliness that hurts people feelings... but still makes us laugh.

Path to late night: Parlayed his popularity as a caller to a Phoenix radio show into a radio career, including a regular gig as Jimmy the Sports Guy on Los Angeles-based KROQ's Kevin and Bean show. Embarked on a TV career that included Comedy Central's The Man Show and Crank Yankers, in which he — yes — makes crank calls.

Big New Promotional Push: The craziest ad ever:

Best Moment: Taking it pretty well when his girlfriend presented him with this.

Weirdest airing of personal business: You saw the Matt Damon video, right?

Craig Ferguson

Show and Time: Late Late Show with Craig Ferguson, CBS, 12:35 am

Years on Air: Jan. 2005-present

Trademark: Brave, self-effacing, surprisingly blunt confessions.

Path to late night: Began performing on the United Kingdom comedy circuit as a character called "Bing Hitler." Broke into television in the U.K., then the U.S., eventually playing Drew Carey's boss on The Drew Carey Show.

Big New Promotional Push: Turning up throughout CBS's prime-time schedule this Monday to remind everyone to tune in to his show.

Best Moment: Discussing his alcoholism and when not to joke about someone:

Weirdest airing of personal business: Revealing his secret marriage — lucky number three — on the air.

Jimmy Fallon:

Show and Time: Late Night with Jimmy Fallon, NBC, 12:35 am

Years on air: The clock starts Monday night.

Trademark: Laughing at his own jokes on Saturday Night Live, and top-notch impersonations everyone forgets he can do.

Path to late night: Always dreamed of appearing on SNL, and got there by way of The Groundlings Theater and performing standup. When he left SNL, executive producer Lorne Michaels suggested he consider taking over as O'Brien's replacement.

Best New Promotional Push: A series of vlogs as he prepares to take to the airwaves.

Best Moment: Getting a talk show. Oh, and this bit of awesomeness.

Weirdest airing of personal business: Besides his admission that things didn't work out so well with making movies? Not much, actually. A New York Times profile a while back suggested a guy with a pretty angst-free life. It was good while it lasted.