A FEW YEARS AGO, I mused about the prospect of Peter Jennings interrupting the nightly news to read ad copy, the same way radio stars like Sean Hannity and Paul Harvey do. Alas, the joke has become reality, with CNBC’s Donny Deutsch doing precisely that, reading a plug for Philips Electronics during his cable talkshow.

Obviously, nobody will ever confuse ad-man Deutsch with newsman Jennings, but this concession to advertisers (in a multifaceted deal that includes sponsorship of “NBC Nightly News”) is the latest shoe to drop in what has been a signature year for TV news — one marked by a slow downward stumble in terms of long-eroding standards.

Many will view this year through the spectrum of Katie Couric’s leap into “The CBS Evening News” anchor chair, which undeniably softened its focus to accommodate her morning-honed skills. Yet the more pertinent moment involved NBC’s plan to dramatically cut costs, mostly at the expense of its news division.

As is so often the case, it took someone with news credentials to swing that kind of ax — in this case, NBC Universal TV Group chief Jeff Zucker, who cut his professional teeth producing the “Today” show. Under Zucker, NBC announced an initiative to strip $750 million from its budget, most of which hinges on dismantling aspects of its news operation.

Beyond that, however, the lowlights just kept coming. A U. of Wisconsin study found almost nonexistent local news coverage of this year’s midterm elections, considered the most significant in years. CNN and “Today” were among the news outlets that interviewed the stars of “Talladega Nights: The Legend of Ricky Bobby” and “Borat” in character, thus functioning as free-floating arms of studio marketing departments. And primetime newsmags continued to traffic heavily in true crime and pedophile sting operations — compelling television, to be sure, but far from the kind of in-depth reporting for which the times cry out.

To be fair, the year also witnessed journalists like ABC News’ Brian Ross doing yeoman work by breaking open the congressional page scandal (online), and Ted Koppel brought his customary class to Discovery Channel, while Dan Rather landed at HDNet — finding niche life after network TV.

Bringing pictures back from Iraq also exacted a dismaying toll on those risking their lives abroad. Both ABC’s Bob Woodruff and CBS’ Kimberly Dozier suffered serious wounds in incidents that also resulted in injuries and death to their respective crews.

In the final analysis, though, the prevailing images of 2006 will almost surely be of news as a punch line serving up comedic fodder for “The Daily Show,” coupled with NBC’s streamlining efforts — which, admittedly, parallel cuts implemented by many newspapers undergoing their own spasms adapting to fit the new-media future.

There will also be the lingering aftertaste (and related lawsuit) associated with Headline News’ Nancy Grace grilling a woman about her missing child, only to have the interview subject later commit suicide; and colleague Glenn Beck asking a Muslim U.S. congressman why he shouldn’t believe that the Democrat is in league with the nation’s enemies.

Lost, too, from both cable and broadcast is any notion, however quaint it sounds, that news shouldn’t be held to the same level of ratings tyranny that governs sitcoms and reality TV shows.

Indeed, Fox News’ Bill O’Reilly could be heard on his radio show last week lamenting that he can’t devote more time to Iraq because the net’s numbers drop every time he ventures into that zone. Given the clout O’Reilly wields in the cable space, it’s an especially lame excuse for retreating to overblown topics like kids in peril and the so-called “war on Christmas.” Nor can the revamped “Nightline” present any better defense for its fluffy turn away from a venerable tradition than crowing “The numbers are up.”

NBC coyly christened its belt-tightening “NBC 2.0,” a reference to that shifting business climate and the technological advances behind these makeovers. Hopefully, the media bloodletting of 2006 will be a memory by this time in ’07, but taking a broader view back of the year that was, it’s time for all of TV news to take a deep breath, and then reboot.