Wow, first the duet together, and the music video together, and now fireside chats with Ellen... this couple should set up a joint twitter account.

Seriously though, here is Katy Perry and John Mayer being all cosy and uncontrived on Ellen's couch by way of promoting their new single Who You Love (and Katy's new fragrance, by all accounts).

Katy also deploys a festive 'chestnut' regarding the authenticity of Kanye's Bound 2 video. One features a load of real couples riding a mechanical bull, the other features Kim Kardashian riding a mechanical bull - the only real difference is the direction Kim's hair is blowing...