• by David Goetzl , May 24, 2006

Looking to establish momentum before Katie Couric takes over the anchor chair at CBS--and perhaps eliminate some uncertainty as the upfront kicks in--ABC has named Charlie Gibson as the new anchor of its "World News Tonight."

Gibson starts the gig Monday, giving him three months to establish himself before Couric debuts to much fanfare and a likely ratings frisson at CBS in September. This also allows ABC to go to market in the imminent upfront with a plan in place for its evening newscast.

Elizabeth Vargas, who was named co-anchor of "World News Tonight" in January, will go on maternity leave starting in August, and then return as an anchor on "20/20" and host of prime-time specials. Vargas and Bob Woodruff officially took over for Peter Jennings as co-anchors of the newscast in January, but it has been a difficult path since with Woodruff suffering severe injuries while reporting in Iraq and third-place CBS making some ratings inroads.

Gibson said in a statement that he is eager for "the broadcast to start a new chapter."

ABC indicated Tuesday that Woodruff will eventually return to "World News Tonight," although the timetable and role are unclear. Woodruff said in a statement: "I look forward to contributing to (Gibson's) broadcast as soon as I'm able."

Gibson will do double duty through June, continuing as co-anchor of "Good Morning America" with Diane Sawyer along with the "World News Tonight" responsibilities. In July, he will leave "GMA."

By September, the former Jennings-Rather-Brokaw evening news lineup will be Gibson, Couric, and NBC's Brian Williams.