Travis Barker and Busta Rhymes collaborating on Transformers 2 song

According to Travis Barker's Twitter page (and first pointed out by the Transformers blog) Barker is working on song with Busta Rhymes for the soundtrack to Transformers 2. He said this:

Listening to a new version of a track I'm playing on for Busta Rhymes for the Transformers 2 soundtrack. Shit is jammin'.