When former President Richard M. Nixon moves into his newly purchased $1-million condominium in New York, his neighbors will include a member of the myserious, moneyed Araneta family of the Philippines.

The Aranetas, whose vast global holdings put them in the Rockefeller and Rothschild category, should have been attracting a lot of attention in the United States recently because another of the clan has become a neighbor of President Carter and his relatives in Plains, Ga.

George Araneta, who is married to a former "Miss World" from Colombia, bought a thousand acres or so near the Carters and turned it into a private hunting preserve. Randy Coleman, who works for Billy Carter, manages the property and gets to say who has permission to take their hound dogs and shotguns in there and who doesn't.

Young Araneta's presence in Plains puzzles the local townfolk. He shows up frequently to take Miss Lillian and Billy to dinner at the Best Western Motel. Once he even took Miss Lillian and her motorcycle-riding daughter Gloria to lunch at a little French cafe known as L'Normandlie in Plains.

George Araneta is more at home and less conspicuous in New York's finer restaurants. He lives on Park Avenue. It is his father who lives at 810 Fifth Avenue, and will soon be close -- geographically at least -- to the Nixon family.

Abraham Hirschfeld, the real-estate entrepreneur from whom the Nixons are buying their new 12-room apartment, calls the senior Araneta "the richest man in Manila."

The family owns, among other things, the ampitheater where Muhammad Ali fought his "the thrilla' in Manila." The family manse is known as "The White House."

The Aranetas definitely are expanding their business interests all over the United States and Canada, but being very hush-hush about it. Their names hardly ever appear in print.

Young George "is better known for marrying a 'Miss World' than anything else," says one State Department source. In the Philippines, that's definitely a status symbol. "They [the rich] all end up with a titled beauty-contestant wife," says one former U.S. ambassador who served there. "I remember when a 'Miss Universe' got off the plane at the airport and someone pinched her. It was nearly an international incident until she found out how rich he was. She ended up marrying the gentleman."

"Grey Gardens," the dilapidated 28-room house where Jacqueline Kennedy Onassis' relatives lived with cats, cobwebs and holes in the roof, has been sold. Washington Post executive editor Benjamin C. Bradlee and his wife, Sally Quinn, bought the house last weekend from Edith Bouvier Beale, a cousin of the former first lady. The house and its occupants, subjects of a documentary movie in 1976, had been the home of Beale and her late mother since 1923. The property, once in East Hampton showplace, received world-wide publicity in the early 1970s when health officials condemned it as unfit for human habitation and threatened the occupants with eviction. At the time, Onassis and her sister, Lee Radziwill, made $32,000 worth of repairs.

In New York, architect I.M. Pei and Barbaralee Diamonstein are sending out invitations to a $40,000 birthday party for 80-year-old sculptor Louis Nevelson, to be given on Wall Street's "Black Friday," Oct. 29. Luchow's, the revived restaurant that has been around almost as long as the guest of honor (78 years), is picking up the tab for the sponsoring Municipal Arts Society, Diamonstein, whose Manhattan apartment, with its valuable Nevelson hanging on the fireplace wall was featured in a two-page spread in Vogue magazine a couple of years ago, is the guest editor of a special "Art News" issue next month which celebrates the 50th anniversary of the Museum of Modern Art. It's titled "I remember MOMA, But I prefer Dada" . . . When deposed Nicaraguan dictator Anastasio Somoza was staying on the Grand Bahamian Island of Exuma recently and seeking sanctuary, he resided in the "Pieces of Eight." The inn is owned by Nigel Bowe, a Bahamian lawyer who is almost the size of "Too Tall" Jones and a man whose name came up frequently in the investigation of Rep. Daniel Flood and a man who could get things done in the Bahamas . . . It is ironic to see Evan Dobelle getting criticized in print recently for throwing money around at the Democratic National Committee. When Dobelle first came to Washington, he took two reporters to lunch at the Madison Hotel's expensive Mountpelier Room and pulled out a five-dollar bill and a one to pay the tab. He was appalled to discover that the $6 (all he had in his pocket) wouldn't pay the tip.