Guess Who Taylor Swift's Never Getting Back With: Mystery Ex Revealed!

Taylor Swift is notorious for writing hit songs about her ex-loves - just ask Joe Jonas, Taylor Lautner and John Mayer! Ever since her catchy new pop single "We Are Never Ever Getting Back Together" hit the airwaves, there's been constant chatter and speculation on who the mystery guy T-Swift is "never ever ever ever getting back together" with. Joe Jonas swears it isn't him, so who could he be?

A source tells Us Weekly that the mystery dude is actually Taylor's ex, Jake Gyllenhaal! 

“It’s definitely about Jake,” says the source. The music video features an actor who looks like Jake and the lyrics are telling too: “Baby, I miss you and I swear I’m gonna change.”

What do you think: is this song really about Jake - why or why not? Who do you think it's about?