NEW YORK – And so on the first day of Year One A.T. (After Tony) the “Sopranos”-viewing world was split in two camps.

One was muttering bitterly into its morning coffee at the open-ended conclusion of the epic series, a banal family moment over onion rings that would have delighted existentialist Jean-Paul Sartre, author of “Being and Nothingness.”

The other was lavishly praising the iconic HBO drama for capturing life’s essential ambiguity and disorderliness.

Forget Tony for a minute – the guy’s been psychoanalyzed for years. Does all this say anything about US?

For some popular culture critics, the two reactions speak to the difference between entertainment and art, and which of them we want. If we wanted pure entertainment, there was obvious disappointment _ no, aggravation _ in a finale that set up threats to Tony’s life in that last diner scene, then ended abruptly.

But if we see it as art, they say, then why should we object to the artist – series creator David Chase, said to be vacationing in a French chateau Monday – painting final brush strokes on his masterpiece as he wishes? And in retrospect, aren’t unanswered questions in perfect keeping with the moral ambiguity that’s infused the whole series? And aren’t loose ends a huge part of life?

“In our popular culture, we’ve come to expect things to get tied up neatly,” said Jerry Herron, a professor at Wayne State University in Michigan, who found the ending brilliant. “The claim that Chase is making as an artist here is, real life doesn’t have neat endings.

“You want Tony blown away? You want him in jail? Chase is saying, ‘Fine, you write that script,'” Herron said. “He’s saying that life goes on, and art goes on, and he’s just going to end it right here.”

Brilliant wasn’t a good enough word for screenwriting professor Richard Walter, of the UCLA Film School, to describe Sunday night’s finale. “That’s too tame,” he said. “This was genius!”

“Sure, I was frustrated,” Walter said of the final cut-to-black as Journey’s “Don’t Stop Believing” played on the jukebox. “But you don’t want everything tied up with a neat ribbon on it. I don’t know what’s going to happen in MY life. Do you know what’s going to happen in yours?”

One thing was clear: around office watercoolers, on blogs and on message boards, people wanted to talk about the finale. Their most immediate question: had the cable gone on the fritz? (The final cut was followed by a few seconds of darkness and silence before the credits rolled.) For some watching on DVRs or TiVo, there was also a moment of fear that the show had run over and they’d missed the ending – a frustration that occurred with this year’s “American Idol” finale.

Nielsen Media Research didn’t immediately have ratings information. However, preliminary estimates indicated viewership at the four biggest broadcast networks was down in double-digit percentages compared to last year. And HBO said its Web site crashed shortly after the episode due to the volume of people checking in and posting messages. There were 364,000 page views a second at its peak – “just astronomical,” said spokesman Jeff Cuson. It took a half hour to get the Web site up again, and an hour for the bulletin boards.

The blogosphere was buzzing as well. On technorati.com, a site that monitors blog activity, the second-most popular term Monday morning was “Sopranos,” after “YouTube.” (It even beat out Paris Hilton, down to No. 4.)

For many fans, there was disappointment, befuddlement, even rage. “YOU GUYS GOT ROBBED – MAJOR BIG TIME!!!!!”, one wrote on HBO’s message board. “David Chase left way too many loose ends dangling in the air, and too many questions unanswered.”

Some critics agreed. “Tony and Gang Whack Fans,” read the front-page headline of the New York Post, which pronounced the finale “spectacularly disappointing.” Yet others argued the opposite. “Chase was true to himself, and that’s what made ‘The Sopranos’ brilliant on Sunday night, and the 85 episodes that went before,” wrote The AP’s Frazier Moore.

Some suspected that Chase had an ulterior motive for pulling his punches, plotwise: a future “Sopranos” movie.

“The line to cancel HBO starts here,” wrote Hollywood analyst Nikke Finke on her Deadline Hollywood Web site. “What a ridiculously disappointing end … Even if David Chase … was demonstrating the existential and endless loop of Tony’s life or the moments before the hit that causes his death, it still robbed the audience of visual closure. And if it were done to segue into a motion picture sequel, then that kind of crass commercialism shouldn’t be tolerated. There’s even buzz that the real ending will only be available on the series’ final DVD. Either way, it was terrible.”

As Monday wore on, however, there was the sense among some people that the ending, so frustrating at first viewing, was a lot more plausible after a night’s sleep.

“I was really annoyed watching it,” said Marlene Windmiller, a New York attorney and mother. “But now as I think about it, it makes more sense. You know, it was what it was. There really was no more left to say.”

To one of the nation’s top television analysts, critiquing the “Sopranos” finale seemed a little like picking apart a famous work of literature – for example, by James Joyce or T.S. Eliot – and saying parts of it don’t work.

“Every critic says this is one of the greatest works of art ever made for the small screen,” said Robert Thompson, of Syracuse University’s Bleier Center for Television and Popular Culture. “You can’t second-guess the artist.”

He compared the ending to that of another popular HBO drama, “Sex and the City,” in which Carrie Bradshaw finally got her man, Mr. Big. “Now, that was satisfying,” Thompson said. But was it real? “You had these independent women pairing off like Noah’s ark,” he said.

“This was disappointing, sure,” said Thompson, who initially thought that Chase, who’d been rumored to have shot three endings, simply forgot to add one of them on. “But you could also say this is what the show needed to do to stay true to itself.”

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