David Westin, who guided ABC News through a tumultous 13-year period, told staffers on Monday that he will retire by the end of the year.

Westin took over for legendary executive Roone Arledge in 1997. Since that time, Westin had to deal with the sudden death of longtime World News Tonight anchor Peter Jennings.

In 2006, Westin named Bob Woodruff and Elizabeth Vargas co-anchors of the evening broadcast. Less than a month later, however, Woodruff was seriously injured covering the war in Iraq.

TVNewser has much more on Westin’s decision to leave ABC News.

New Career Opportunities Daily: The best jobs in media.

America Ferrera and John Mayer

It’s arguably the most exclusive magazine party of the year. (Graydon Carter‘s Vanity’s Fair Oscar party perhaps being the other.) John Edwards mingled with John Mayer. Sir Richard Branson (just back from dogsledding in Alaska) commandeered the corner of the bar like a Virgin spaceship, and allowed Henry Kissinger to ride co-pilot. Craigslist’s Craig Newmark chatted up Wikipedia’s Jimmy Wales. New England Patriots coach Bill Belichick walked through the cocktail hour unrecognized. Michael J. Fox, too, virtually unnoticed, chatted with Elizabeth Vargas near the glass window overlooking Central Park. Arianna Huffington was noticed. (Line uttered in every pre-dinner conversation: “Is that someone? It looks like someone, I don’t know … do you?”)

Time Warner execs — like Richard Parsons and Jeffrey Bewkes — buzzed along the edges as the usual media-on-media action (including Ad Age‘s Nat Ives, WWD‘s Stephanie Smith, Jossip’s David Hauslaib, New York mag’s Jesse Oxfeld, Gawker’s Lockhart Steele and Doree Shafrir, ETP’s Rachel Sklar, Glynnis MacNicol, Julia Allison, Radar‘s Jeff Bercovici, NYO‘s Michael Calderone) made nice use of the open bar.

But as much firepower as there was at last night’s Time 100 party at Jazz at Lincoln Center, just 36 of the 100 to make 2007′s “most influential people in the world” list made it, and there were plenty of notable no-shows: No Obama. No Borat. No Queen of England. Rosie. No Leo. No Gore. No Timberlake. No Tyra.

But impassioned speeches — delivered over dinner by Elizabeth Edwards, Brian Williams, Bloomberg (with an ode to late Boston Celtics’ exec Red Auerbach — huh?) Branson and others — and a three-song set by Mayer more than made up for the relative lack of A-listers.

Others spotted during cocktail hour: Cate Blanchett, Mayor Bloomberg, Queen Rania Al-Abdullah of Jordan, Simon Fuller, Charlie Rose, Tina Fey, Mario Cuomo, Martha Stewart, Brian Grazer, Gayle King (no Oprah), Matt Lauer, Chris Matthews, Brian Williams, Ziyi Zhang, Police Commisioner Ray Kelly, Suzanne Vega, Harvey Weinstein, David Lauren and Lauren Bush.

FishbowlNY’s Coverage Of Last Year’s Time 100:

New Career Opportunities Daily: The best jobs in media.