London's Olympic logo.
The jagged emblem, based on the date 2012, comes in a series of shades of pink, blue, green and orange and will evolve in the run-up to the Games.
The word London and the Olympic rings are included in the first two digits of the new logo.
"This is the vision at the very heart of our brand," said London 2012 organising committee chairman Seb Coe.
"It will define the venues we build and the Games we hold and act as a reminder of our promise to use the Olympic spirit to inspire everyone and reach out to young people around the world