Derrel is spot on from my experience. People in the field who may be using a sat phone or their cell to transmit photos back to the editor don't want files that are 40 megapixels. It's not that there isn't value in having a ton of megapixels available. It's that for most journalists, you are expected to do very little editing--maybe some cropping, exposure, sharpening. But you're not supposed to substantially change the image through your edits.