Kellie Pickler's upcoming sophomore album boasts a co-write with her good buddy, Taylor Swift. The blond beauties became fast friends while on the road together last year for Brad Paisley's Bonfires & Amplifiers Tour. They spent a lot of their free time writing tunes together, and one particularly vengeful song made the cut for Pickler's new CD.

"I'm really crossing my fingers that it'll be a single, because it's the best song ever," Swift recently gushed to GAC.

"It most definitely probably will be," Pickler added. "And it's a song about her ex-boyfriend, 'cause that's the only kind of song I know how to write."

"She is notorious for writing songs about exes, and they're always really nice, very lovely songs," Swift continued. "Don't [tick] her off, or she'll write a mean song about you!"

Pickler's album, simply titled 'Kellie Pickler,' is due for release on September 30. Swift is also busy writing and recording for her new album, due later in the fall.