Which Apple Store Is the Largest in the World?

Rumors are swirling that Apple is planning to build a retail store in NYC's Grand Central Terminal. The train station, which serves the Metro North commuter lines traveling north upstate and to Connecticut, is located on the east side of the city, and the rumors say that the store will be located right inside the terminal, not in one of the adjoining retail spaces.

If reports are true, this store would be the largest in the world. Can you guess which store holds the title now?