VIDEO: ONE DIRECTION Rocks the Plaza on 'Today'

One Direction drew an estimated 18,000 'Directioners' to Rockefeller Center this morning, all packing into about two New York City blocks outside a temporarily renamed Studio 1D. The fans arrived in anticipation of the group's performance as part of Today's Toyota Summer Concert series. Check out the appearance below!

As a result of the concert, he morning show is trending worldwide on Twitter, and has been since 7:05 a.m. ET, hours before the start of the concert.