Taylor Swift brings famous pal on stage:

Top Shots of the Week Photos | Top Shots of the Week Pictures - Yahoo! OMG!: Fans got two for the price of one during Taylor Swift's big concert at Madison Square Garden on Tuesday night, when Selena Gomez showed up on the stage to perform a duet with her pal! "One of my best friends is such an amazing singer and after four years of being best friends we have never stepped on stage together and I think that's such a shame," Taylor teased from the stage. "So it just so happens that Selena is here tonight." The two sang Selena's hit "Who Says." (11/22/2011) less