Justin Bieber is really pulling out the big guns for his upcoming album, 'Believe.' Not only is the teen superstar working with hitmaker Timbaland, but it appears he's also collaborating with super-producer Pharrell Williams too. We're sensing that some dance hits will surely be emanating from 'Believe.'

Elsewhere on Twitter, Missy Elliott lent a hand to Grammy-nominated, J.Cole. It seems like Elliott will be featured in a forthcoming J.Cole video. Any guesses on what it might be?

Chris Martin of Coldplay was busy rehearsing for the Grammys with duet-partner Rihanna, and Demi Lovato was looking for that special someone to spend Valentine's Day with.

Read what your favorite stars were chirping about this week!