Things are heating up so fast!
According to Us Weekly, Swift is on cloud nine right now:
[Image via Forty Seven/WENN.]
This time, however, the Coldplay singer let his fingers do the walking while RiRi herself came on stage to do the talking!
Check out the duo's INCREDIBLE performance (above) of her 2007 smash single during the band's Mylo Xyloto tour stop in Paris, France.