Talk about Moneyball. With a new estimated value of $2.3 billion, the Yankees are the most valuable franchise in American sports, riding the surging tide of television revenues lifting every team in Major League Baseball’s yacht club. The Bombers — who were valued at $1.85 billion in last year’s rankings — topped this year’s edition of Forbes’ annual ranking of MLB organizations, and surpassed even the $2.1 billion Dallas Cowboys as the most valuable franchise in North America, according to the magazine. The numbers were actually conservative, a fact exemplified by the runnerup Los Angeles Dodgers, who are pegged at $1.6 billion in the Forbes survey even though the team sold last year for $2.15 billion. “If the Yankees were ever on the block, it would probably be $1 billion more than what (Forbes) has,” a baseball insider said. “Forbes is doing it based on numbers. They do it based upon a conservative estimate of revenues, expenses and then put a conservative multiple on it. I also think the Mets are worth a lot more.” The Mets, with a valuation of $811 million, were sixth on Forbes’ list behind the Red Sox, Cubs and Phillies. “I think they’d be worth a lot more than that on the open market,” said the baseball insider. “When you get into an auction, it’s basically, how bad does a rich person want it?” Forbes assessed cash flow, assets and debts of each franchise. Its formula doesn’t account for the intangible egotism and competitiveness that drive titans of industry to buy a professional sports team (George Steinbrenner once said owning the Yankees was “like owning the Mona Lisa”).