Arri has announced a new AlexaXT Line up. There will be four new XT Cameras: Alexa XT, Alexa Plus XT, Alexa Studio XT, Alexa M XT. All 4:3 sensors, in-camera ND as well as possbile ArriRaw internally.
Read more. http://www.fdtimes.com/2013/02/20/arri-alexa-xr-and-xt/