The final episode of Oprah Winfrey’s syndicated talk show last month averaged 89.57 million fewer viewers than did the finale of “M*A*S*H.”

Oprah’s camp ran ads for her May 25 series finale in which her swan-song episode was likened to, among other iconic TV moments, the series finale of the long-running CBS antiwar dramedy — a finale that remains the most-watched TV broadcast in history in terms of percentage of the country’s population tuning in.

So, because Oprah’s camp brought it up:

“The Oprah Winfrey Show” finale averaged 16.4 million viewers, Nielsen said Wednesday.

The “M*A*S*H” finale, on Feb. 28, 1983, averaged 105.97 million viewers.

Oprah’s ad promoting her final episode as queen of daytime talk TV also invoked Johnny Carson’s final night hosting NBC’s “The Tonight Show.”

Sigh.

Carson’s final night on “The Tonight Show,” on May 22, 1992, averaged 41.4 million viewers.

Oprah’s finale came just 25 million viewers short of that.

Now that, I hope, we’ve cleared that up:

More people also watched the final two nights of dancing on ABC’s “Dancing With the Stars” and the final two nights of singing on Fox’s “American Idol” during the final week of the 2010-11 TV season than watched the three-day-long laying to rest of Winfrey’s syndicated show that week.

On the other hand, getting 16.4 million people to watch you, smack dab in the middle of a workday, as you stand onstage for an hour, jewels dripping from your wrist and ears, and lecture them about the lessons that have been the anchor of your life, is no small accomplishment.

And what of the Oprah show’s two orgies of celebrity excess leading up to the finale, collectively called, “Surprise Oprah! A Farewell Spectacular”?

Well, the Monday version, in which Beyonce and her all-girl dance troupe did a Girl Power bump and grind while dressed as graduating co-ed strippers, attracted average audiences of 12.3 million.

A slightly larger crowd of 13 million watched the second day of “Surprise Oprah!” in which Michael Jordan offered Oprah a job if she needed one, Simon Cowell patronizingly pronounced Oprah a good kisser and Arnold Schwarzenegger’s wife, Maria Shriver, put “love,” “support” and “the truth” at the top of her Important Things list.

While those numbers are much bigger than the Oprah show’s May average of 8.2 million viewers, they are not the biggest crowds TV shows gathered that week.

Scotty McCreery’s crowning as the new “American Idol” winner was that week’s most-watched show. Scotty snared 29.3 million viewers — nearly 13 million more than Oprah.

The “Dancing With the Stars” final Monday episode was second, with an average of nearly 23 million, followed by the “Dancing” finale, which logged 21.4 million, and “Idol’s” final competition night, which attracted nearly 21 million.

On the bright side, the final three episodes of “The Oprah Winfrey Show” rank fifth, sixth and seventh for the week — beating everything in prime time that wasn’t related to “Idol” or “Dancing,” including, for instance, the much-ballyhooed season end of “Glee,” in which the glee club finally went to nationals.

Vieira’s goodbye

Meredith Vieira gamely played Ring Around the Rosie with Carole King at a piano, then let herself be dragged around Rockefeller Plaza in a “Glee”-ish musical tribute as she said goodbye to NBC’s “Today” on Wednesday.

“Welcome to ‘Today’ on a very bittersweet Wednesday morning,” co-host Matt Lauer said at the very top of the show.

“Looks like I’m leaving,” Meredith joked.

“Mixed emotions?” Matt asked. This, pookies, illustrates why you must never ever take a bet as to whether the words “bittersweet” and “mixed emotions” will be used in the first three minutes of someone’s final episode on a talk show of any kind. Because “bittersweet” and “mixed emotions” are to series finales what “Don’t ever change” is to high-school yearbook inscriptions.

“We’re going to pay tribute to Meredith throughout the morning and have a number of surprises as well,” Matt warned at the top of the broadcast.

True to Matt’s word, King was trotted out to sing “You’ve Got a Friend” because, Matt said, Meredith sang it like 30 times the day she graduated high school. Meredith, Matt and the “Today” show gang sat on the sofa while King crooned at the baby grand. Only it’s a slow-moving, long-ish tune, so after a few bars, Matt decided to spontaneously lead Meredith over to the piano — with Ann Curry, the show’s newsreader, who is replacing Meredith, Al Roker, et al., not about to be left behind. Except they had their backs to the camera, so they swung around behind King, then swung around some more, then some more.

Live TV is really hard.

Later, Meredith took off her bone-colored heels in favor of sensible black shoes so she could be “surprised” with a starring role in a live-music-video-cum-flash-mob to the enough-already Journey anthem “Don’t Stop Believin’.”

Meredith, huffed, puffed and jogged from the studio, through the control room, past the offices, up some stairs and outside to Rockefeller Plaza, where “Today” cast and crew flash mobbed her, kissing Abe Vigoda and being guitar-lick-mimed by Jimmy Fallon along the way.

Then it was time for the “Today” gang to remark how un-Katie-Couric-like Meredith had been lo these past five years.

“I have never, in my entire career, worked with anybody who has been more about the program and the people they worked with than themselves than you,” gushed Al, who had earlier called Vieira’s “Today” tenure “five of the greatest years of our lives.”

“I have marveled over the fact someone with talent as large as yours, how small your ego is,” Matt added. “You’ve taught us all how to be great teammates, and that’s the gift I will take away from you. So thank you so much.”

Vieira joined the morning infotainment show in ’06, stepping in for Couric, who left to replace Dan Rather as anchor of CBS’s evening newscast. Couric recently left that gig and has announced she’s going to do a syndicated talk show for Disney that will air on ABC’s larger stations — just as Oprah’s did.

“I want to speak for just a second on behalf of all the viewers who want to thank you, if they could be here today, for getting up at 2 a.m. every morning to ask the hard questions, five days a week, on weekdays, every morning, to make us laugh and to remind us, all the way till now, to live our values,” added Ann, who spent the entire two hours leaning forward to suggest earnestness.

“Our door is always open. We are always your family,” Ann said.

“I don’t want to go now. I want to stay,” Meredith responded to all the affection.

Grievously, the camera was not on Ann at that moment.

Fishburne’s exit

Laurence Fishburne is leaving “CSI.”

Fishburne joined the show in December 2008, stepping in when William Petersen bowed out. The move did not work out as well as hoped.

During the 2007-08 TV season — Petersen’s last on the show — “CSI” averaged 17 million viewers and was ranked ninth among all programs. (“CSI” ranked No. 14 among the 18-to-49-year-olds advertisers crave and ranked No. 13 among the 25-to-54-year-old viewers with whom CBS is usually quite strong.)

This past season, however, “CSI” averaged 13.6 million viewers and took a particularly big hit among those 18-to-49-year-olds, dropping to No. 29.

The show’s other star, Marg Helgenberger, has told People magazine that she will be in only a few episodes this coming season. The crime procedural will be moved from its traditional Thursday night to make room for “Person of Interest,” a new J.J. Abrams drama starring Michael Emerson.