At Wembley Stadium for Live Earth: host Chris Moyles has just tried to sell a used 4x4 to two billion people watching the great eco-event. The atmosphere is indeed amazing. Uh-oh. Genesis -combined age 380 - have tottered on stage and struck up Turn It On Again. Is this a terrible warning from Al Gore? Unless we cut our carbon emissions at once, all the ancient supergroups will re-form: Yes, ELP, perhaps even (gulp) Jethro Tull. It is a terrifying prospect. Phil Collins is belting out Invisible Touch now. We have a duty to future generations to act.