(LOS ANGELES) -- On Tuesday evening, Jimmy Kimmel steered his 10-year-old late-night show into some competitive comedic waters, bringing it on a collision course with Jay Leno and David Letterman at 11:35 p.m. Eastern time.
ABC moved Jimmy Kimmel Live! into the Nightline time slot and shifted the ABC News program to 12:35 a.m.
NBC execs made good on a plan to bump The Tonight Show with Jay Leno to 11:34 in response -- a move Kimmel sarcastically called "interesting" earlier in the week -- but Leno, who Kimmel recently called a "sell-out," made no obvious mention of the switch.
On CBS' The Late Show with David Letterman, Kimmel's comedy idol, Letterman, welcomed JKL! saying, "Come on in, Jimmy! Why should we have all the fun here?"
Paul Shaffer echoed the well-wishes, saying "Change that landscape, Jimmy!"
During his monologue, Kimmel thanked ABC execs for their "vote of confidence," saying he doesn't take the responsibility lightly, "especially now with a Kanye West/Kim Kardashian baby on the way. This is the time when I shine bright like a diamond."
Kimmel's first guest was his pal Jennifer Aniston, who not only smashed what she thought was Kimmel's old desk with a sledgehammer, but also shared pictures of a vacation she took with Kimmel, her fiancee Justin Theroux, and another Kimmel pal, John Krasinksi from The Office.
Aniston, who cut schoolmates' hair as a youngster, also gave Jimmy a trim.
No Doubt was his musical guest, blasting out "Push and Shove," the title cut from their new album, as well as an older favorite, "Hella Good."
Jimmy Kimmel Live!'s guest lineup for the rest of the week includes Ryan Gosling, Mark Wahlberg, Jamie Foxx, Sofia Vergara, Ellen DeGeneres, and Kim and Kourtney Kardashian.
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