New York ? The New Jersey Nets were officially sold Friday to a Brooklyn developer intent on moving them across the Hudson River — a move immediately hailed in New York for returning big-time sports to the borough.

Duke Snider, meet Jason Kidd.

“It’s taken 47 years, but today we can finally say we’ve corrected the great mistake of ’57,” said Brooklyn borough president Marty Markowitz, referring to the Dodgers’ defection to California.

New owner Bruce Ratner was joined at a gala news conference by an assortment of politicians, Brooklyn-born ex-Knicks standout Bernard King, and rapper Jay-Z, a fellow investor. At King’s invitation, all donned “Brooklyn Nets” jerseys.

“It’s a great day for all of us,” said Ratner in his first public comments since the sale was announced Wednesday. “It’s a great day for Brooklyn.”

Ratner spoke shortly after the Nets’ former owners, YankeeNets, voted in a teleconference to approve the deal. The rest of the NBA owners must approve the deal as well.

NBA deputy commissioner Russ Granik, at the Nets-Heat game Friday night in Miami, said the possibility of a team in Brookyln was interesting.

“There certainly isn’t any predisposition against it. Obviously we don’t like to see teams moving around a lot, but on the other hand this is a move within the same territory. In those cases franchises are usually given a fair amount of latitude,” he said.

While best known as the spurned home of baseball’s Dodgers, Brooklyn has produced a fair number of basketball standouts: coaches Lenny Wilkens of the New York Knicks and Larry Brown of the Detroit Pistons, current Knicks guard Stephon Marbury, and ex-NBA players Chris Mullin and Billy Cunningham.

But lurking behind the celebration were threats from neighborhood groups regarding the construction of the proposed arena. Ratner estimates about 150 homes would be affected, although neighbors fear the number will be closer to 1,000.

“Until meaningful discussions with the community are granted, we cannot wholeheartedly support this proposition,” said the Rev. Herbert Daughtry, a veteran activist whose church sits two blocks from the proposed site. “We know that all that glitters is not gold.”

Ratner promised that he would involve local residents as the $2.5 billion project, with its 19,000-seat area, moves toward completion.

“It is about the community, and listening to the community, and involving the community,” Ratner said.

Mayor Michael Bloomberg said the project would generate an estimated $400 million in annual economic activity, and create 10,000 new jobs during its construction.