Network executives are by definition anxious people.

Gambling millions of dollars per hour on entertainment for the mainstream masses, the broadcast bosses are afraid to miss a trend, yet equally skittish about getting too far ahead of the curve.

They live and die by overnight ratings, congressional hearings and shareholder meetings. And they know that longevity in the job is unlikely.

This year, underscoring the fleeting, fear-driven nature of the business, a number of top network executives were fired before their projects could get on the air.

Ironically, some of the most promising pilots you’ll see in September were developed by since-axed network chiefs.

Next week in Los Angeles, several new network honchos will offer glowing presentations of their primetime wares for 2004-05 before a gathering of TV critics. Each network chief can be expected to explain - with help from charts, graphs, TelePrompTers and Hollywood star power - why his or her shows are superior.

In their inaugural news conferences, the incoming network presidents will celebrate their new comedies and dramas as sales tools, if not as entertainment offerings. And they will praise their recently dumped predecessors.

At ABC in particular, where the pilots look better than they have in years, the executives crowing about their lineups can’t take credit for them. The current ABC bosses inherited the schedules they are now selling.

If they do not improve the ratings, they too will be history by the time the 2005-06 season is unveiled.

Here’s a network-by-network look at the suit shuffle.

ABC

ABC’s two top executives were booted by parent Disney this spring, sending a message of continued chaos at the lagging network. Chairman Lloyd Braun and president Susan Lyne were fired. His departure was expected, hers was not.

Lyne’s claim to fame was keeping "8 Simple Rules for Dating My Teenage Daughter" running after John Ritter’s death. She acknowledged putting too many reality shows on the air, admitted she was embarrassed about "Are You Hot?" and left the network in a distant fourth place.

ABC Cable Networks president Anne Sweeney steps in to lead the struggling ABC Television Network. Steve McPherson of Disney’s Touchstone Television becomes president of ABC Primetime Entertainment.

ABC has some of the most promising pilots this year, notably the clever soap "Desperate Housewives," from the writer of "Melrose Place"; a drama called "Lost," a sort of "Lord of the Flies" concept about the survivors of a plane crash, from J.J. Abrams ("Felicity," "Alias"); and "Blind Justice," from Steven Bochco ("NYPD Blue"). All were developed on the Lyne-Braun watch.

Additionally, the reality series they launched, "Wife Swap," is touted as ABC’s next possible franchise. "Husband Swap" and "Boss Swap" are already in development.

Best pilot: "Lost."

CBS

The Tiffany network is stressing stability and continuity.

"CBS just completed the 2003-2004 season as America’s most-watched network (again) and the only major network to post year-to-year growth," said the communiqué to critics. "This fall, CBS is adding only five new shows to round out an already strong primetime schedule that includes many hit and returning series as a result of a strong development track record over the last few years."

Behind the scenes, the big cheese at CBS, Leslie Moonves, is now a contender to become the Biggest Cheese at Viacom, CBS’s corporate parent. Departing Viacom chief Sumner Redstone named Moonves and Tom Freston, MTV Networks boss, to split his job as co-presidents of the entertainment conglomerate. Insiders wonder whether Moonves’ attention will be drawn away from day-to-day CBS programming matters.

Moonves, who emerged unscathed from the Janet Jackson Super Bowl episode, assures critics that he is not looking to a future job, that he still attends casting sessions, reads pilots and loves the details of the network business.

Best pilot: "Clubhouse," from Mel Gibson’s company, a coming-of-age story about a batboy for a New York baseball team.

Fox

Gail Berman, president of Fox Entertainment, has made waves for supposedly "revolutionizing" the schedule of year-round rollouts, avoiding the fall rush and debuting shows throughout the year. In fact, Fox is simply working around the restraints of its baseball schedule through October.

The Fox schedule, with premieres in June, November and January, presents a challenge to even the grid-savviest viewer. Berman has a new boss, Ed Wilson, formerly of NBC, who was named Fox Television Network president in May.

Best pilot: "The Jury," from Tom Fontana and Barry Levinson, already on the air.

NBC

Kevin Reilly has been named president of NBC Entertainment, succeeding Jeff Zucker, who moves upstairs - and back to New York. Reilly put "The Shield" and "Nip/Tuck" on FX, moves that put the channel on the programming map. Can he bring edgier, more risqué and youthful programming to the broadcast network so it can compete with cable?

Reilly will conduct his first NBC news conference with critics via satellite from his honeymoon.

Best pilot: Nothing screened so far. Maybe "Law & Order: Trial by Jury."

The WB

Chief executive Jordan Levin was booted at the WB last month. WB chairman Garth Ancier, who was in an uneasy power-sharing situation with Levin (they called it the "kitchen cabinet"), emerged victorious. The network offered to demote Levin, who had been with the network since its launch a decade ago; he chose to walk.

Ancier reports to Barry Meyer, chairman and CEO of Warner Bros. Entertainment. The industry buzz: Levin took the fall for the WB’s underwhelming ratings performance in the just-completed season.

Best pilot: "Jack & Bobby," about brothers in a political family that’s not the Kennedys and how they grew up. From Greg Berlanti ("Everwood," "Dawson’s Creek") and Thomas Schlamme ("The West Wing," "Ally McBeal").

TV critic Joanne Ostrow can be reached at 303-820-1830 or at jostrow @denverpost.com .