On October 10, the incredible happened when a member of the GDC found a video of Billie Joe working in a studio (with Butch Vig looking on). The video contains an intriguing teaser for a new song and begins with Billie Joe apparently playing the second guitar part. In the second section, Billie Joe and others are listening to playbacks with other instruments included. This not only prooves the album was being worked on but also Butch Vig was producing.
Second VideoOctober 14, just before midnight, brought another video was discovered. This video is slightly longer and contains more varied content. It begins with Tre playing drums, shows an FM transmitter (displaying the possibly meaningful number 98.50) while some faint music plays, cuts to Jason Freese walking in and greeting the guys (as well as congratulating Mike on his new baby, Brixton, and making funny faces for the camera), and finishes up showing Mike playing bass in the studio with another appearance by Butch Vig. Not long afterwards, the studio in both youtube videos was identified as Ocean Way, the same studio where American Idiot was recorded.
Link to Green Day's youtube channel contaning both videos