London's iconic red buses are recognised the world over, even if the traditional Routemaster buses, with an open rear platform and on-board conductor to collect fares, have been phased out. Officially withdrawn from general service in London on 9 December 2005, nowadays these once prolific buses have largely been replaced by those of the ‘bendy’ kind and can only be found on certain heritage routes. However, such is the popularity of the Routemaster that calls continue to be made for a new version of the vehicle to be produced. After becoming London Mayor in 2008 Boris Johnson announced the withdrawal of the bendy buses and the introduction of a new hybrid Routemaster by 2012.