On the BlackMagic Production Camera (BMPC) I noticed that it shoots in only 1 of 2 sizes, either Ultra HD 3840x2160 or Full HD 1920x1080. The sensors native resolution is Ultra HD. So how does BlackMagic get down to the 1080 resolution? Line skipping? Crop sensor? Nope. Good old fashioned down-sampled horsepower in the camera. This is important and in contrast to other cameras (I'm looking at you, RED Scarlet). The BMPC does a straight down sample of the 4K image to 1080. So if you shoot at a reduced resolution you don't crop the sensor or start line-skipping on the camera to get down to 1080p (which would introduce large amounts of moiré like on all DSLR's). Instead the BMPC took a page from the Canon Cinema line. The C300 has a chip that captures a 4K image, but down-samples that in camera to 1080p (or 720p). This creates pristine images and avoids many of the problems that DSLR cameras face.
The more I learn about this camera, the better it sounds. Have a look at this video put together by FreshDV talking to a BlackMagic rep about the BMPC and the new BlackMagic Pocket Cinema Camera.