Finally, the collaboration rumors can be put to rest. Justin Bieber and Cody Simpson are really working together! Simpson, 15, tweeted a picture of him and Bieber, almost 18, sitting in the studio together working on some tracks. Can you imagine the kind of fandemonium that will ensue after this single gets released? Angels and Beliebers will be going nuts!

The Aussie and Canadian heartthrobs have been teasing a collaboration for months now, and now the duo are recording a duet together. On Jan. 26, Simpson tweeted, "chilled with the mate @justinbieber in the studio tonight. look for some great records coming."

Simpson later tweeted the black-and-white picture of the duo hard at work, writing, "in the lab. @justinbieber's #Believe will be incredible. & I have an incredible debut album coming also #YoungBoyClass." From the sound of things, the duet will appear on Bieber's upcoming album 'Believe,' which is set to drop some time in the first half of 2012.

Now, we're not sure if the "Young Boy Class" hashtag is referring to Simpson's debut album, also set for a 2012 release, but it just might be considering how dapper and grown-up the teen has been looking and acting lately. He even has a (rumored) girlfriend now, just like his man the Biebs!

Cody Simpson is currently on his Welcome to Paradise tour, while Justin Bieber was recently spotted at a Michael Jackson tribute ceremony at Grauman's Chinese Theater. Both of the singers are also continuing to work on their 2012 albums in the meantime.