Apple is scheduled to hold a special media event on March 2 in San Francisco, at which it will unveil the second-generation iPad. Citing several sources close to the situation, AllThingsD reports that the date is firm, and that the Yerba Buena Center for the Arts is the likely venue; notably, it served as the venue for Apple’s original iPad media event, as well. Apple has yet to send out invitations to media members officially confirming the…