2012 Omega Speedmaster Limited Edition.
In a way, a new Omega Speedmaster for limited edition is not really news. Omega has released a large number of limited edition Omega Speedmasters celebrating milestones in space exploration. Back in 2010 Omega even released the OMEGA Speedmaster Professional Apollo-Soyuz 35th Anniversary watch. A 35th Anniversary is something which you don't normally expected a limited edition watch to be released for.
In 2012, Omega has a good reason to release a limited edition Omega Speedmaster. This year is the 50th anniversary of John Glenn's flight piloting Freedom 7 into orbit around the earth, the first Astronaut ever to do so. I think it is a fairly good guess that Omega would not let such a historic occasion pass without a limited edition Speedmaster to commemorate the event.