Eff Oh, get a job on a shiny new jet and you'll get the chance to join the 'stars in their eyes' brigade, Joking apart, they are far from 'grainy images' that Carnage suggests. Maybe good idea of having one pointed backwards to the cabin too, maybe the image can be super-imposed on the ND, just like the Wx radar. Good chance to really decide which cc member you're gonna pick for the night?...Sorry, couldn't resist that!
On a serious note, such videos can only enhance security and provide another 'feel good factor' for the passengers. It might also stop them asking the stupid questions you normally get on a flight deck visit, although I accept flight deck visits are probably a thing of the past. Shame.