January 22, 1984

LAST week began well for Walter Yetnikoff, president of CBS Records. On Monday, Michael Jackson's ''Thriller'' album, which has sold 21 million copies under CBS's Epic label, got 12 nominations for Grammy Awards, the record industry's answer to Hollywood's Oscars. That night, the young performer walked away with most of the American Music Awards. But on Tuesday, the music turned sour: the Supreme Court, in the Betamax decision, upheld the legality of television taping at home and dealt a blow to the record industry, which has lost billions in sales to the unauthorized taping of music. On balance, however, CBS Records is on a roll, and so is Mr. Yetnikoff. ''This has been the best year we've ever had for CBS Records profits,'' he said, in an office tiled in ''platinums,'' the prizes handed out by the Recording Industry Association of America for albums that sell over 1 million copies and singles that sell over 2 million.

In a restaurant five minutes from the Cinecitta studios in Rome, Federico Fellini, the undisputed superstar of Italian film, was having lunch. With him was his entourage - his writers, editor, press representative and other colleagues from the set. People came over to the table, including Marcello Mastroianni, to greet the Maestro, as everybody called him, to hug or kiss him or just to say affectionately, ''Ciao, Federico, ciao.'' Mr. Fellini is what you would expect: expansive, grand, charming, witty, gracious, and thoroughly himself - like a character from his films. There is also another Fellini: thoughtful, intelligent, wise, and completely realistic. Over lunch, both Fellinis appeared.

AS condominium officers have discovered over the years to their chagrin, the arrival of new unit owners can often trigger trouble. Some newcomers are only vaguely aware of the condominium's rules; others know the rules but nevertheless resist furiously when they are told they cannot let their dog run free or leave their car anywhere they choose. Not all new neighbors are troublesome, of course, but there is now sufficient concern among residents of both city and suburban condominiums to spur the introduction of more comprehensive admissions and screening procedures. In the past, buying a condominium tended to be similar to buying a single-family house. If buyer and seller agreed on a price and the bank approved the mortgage, nobody else entered the picture.

No doubt you've seen a woman who looks like Woody Allen's latest heroine somewhere, someplace before - certainly not in one of Mr. Allen's earlier films, but maybe sipping daiquiris at the bar in Caesar's Palace or chain-smoking in some chintzy nightclub in New York. She wears ruffled shirts, tight slacks and a gold name chain around her neck; keeps her blonde hair teased in a 1950's ''do''; and she never goes anywhere - even at night - without a pair of sunglasses clamped firmly on her nose. When we first meet Tina Vitale in ''Broadway Danny Rose,'' she is screaming - in a nasal Brooklyn accent - at her fickle boyfriend on the phone. ''I don't buy it,'' she says, chomping fiercely on a stick of gum. ''You're lucky I don't stick an ice pick in your goddamned chest.'' Tina, an interior decorator with a penchant for jungle-motif rooms, happens to be the mistress of Lou Canova, a small-time nightclub singer, who is managed by the movie's title character - the hapless Danny Rose. Danny Rose is played by Mr. Allen; and Tina, by Mia Farrow.

O nly 52 percent of the people who were eligible to vote in the last Presidential election did vote, a fact that may be regarded angrily, mournfully or simply shrugged off. Undeniably, however, in any measure of voter participation, the United States is near or at the bottom of the list of Western democracies. Moreover, in the past 20 years the percentage of people eligible to vote who did not vote has risen steadily. ''Who or what is responsible?'' an admirable ABC program, ''Voting for Democracy,'' asks right off the bat at 12:30 P.M. today, and then goes on to identify, if not the who's, then at least some what's. One what scarcely mentioned, however, is television itself. Voting statistics, in their way, are almost as tricky as crime statistics. Clever people can turn them on their head. Demographers, for instance, can prove that the decline in voter turnout has to do with age: When the population is young, the turnout falls off because young people do not vote as regularly as older people. Therefore, when the population ages, voter turnout will increase. At the same time, the less well educated do not vote as often as the well educated, and the poor vote less often than the rich. Along with age differences, you must factor in socio-economic status, too. The decline in voter turnout defies simple explanation.