This week’s announcement that U.S. officials have given tentative approval to Virgin America Airlines to commence operations at San Francisco International Airport is good news for the San Mateo County economy. It will mean an estimated 1,600 new jobs within two years of the airline’s launch. Virgin America’s corporate headquarters is in Burlingame. Combined with the return of both Southwest Airlines and JetBlue Airways to SFO, Virgin America’s presence figures to be a plus for the Peninsula’s travel industry, not to mention local taxing authorities which stand to reap a harvest of fresh funds too. Five-and-a-half years after the events of Sept. 11, 2001, things are looking up.