AllThingsD says that Apple will introduce the iPad 3 next weeks

John Paczkowski from AllThingsD makes sure that the new iPad 3 will be present the first week of March. The event will be in San Francisco, at the Yerba Buena Center for the Arts, Apple’s preferred location for big announcements like these. He reckon that the iPad 3 will be available for purchase a week or so after the event in Apple's stores and on the internet too.
About the technical specs, this tablet is going to be with the same design as the iPad 2, but running a faster chip, having a best graphics processing unit and having a great 9'7 inches with a 2048x1536 resolution on a retina display which will be made it by Sharp. On the other hand, the battery is bigger with 10 hours of autonomy but I think that would be less becuase this fantastic display spends a lot of energy.
Here some spy photos about the iPad 3.

iPad 2 vs. iPad 3

A new mother board will be present with the iPad 3