Fans at Taylor Swift's Newark, NJ concerts got an extra treat this past week - some guest singers joined her on stage. On Thursday (March 28th), Neon Trees member Tyler Glenn joined Taylor for a rendition of the band's hit song, "Everybody Talks."

Train's lead singer Pat Monahan swung by Friday's (March 29th) show to sing "Drive By.

Taylor's tour continues all the way through the summer.  What other surprises do you think she has in store for fans?