Life on Mars?

I've been following the Mars rovers Spirit and Opportunity with great interest since they arrived on the surface of Mars. The complexities of managing two robots and the associated software from millions of miles away intrigue me, particularly the way they diagnosed the flash memory problems on Spirit with almost no information to work from. Now NASA are about to hold a press conference during which they will announce significant findings from Opportunity. This will be webcasted live on NASA TV at 2pm EST / 7pm GMT.

Have they confirmed the presence of water on Mars? Or have they met little green men? Or is it just a publicity stunt to spark interest in the projects? We'll soon see...