This is a very interesting discussion and one I find particularly amusing given than Bruce Dale, an exclusive photographer for NG for over thirty years, has completely abandoned his wet darkroom for digital processing in the past six years. He still uses various film cameras, but is also doing lots of digital imaging in the field as well. He states clearly on his site that cameras of all types are simply tools. He chooses what he thinks are the best tools for making particular images.
National Geographics contest editor displays a lot of arrogance and bias in the statements quoted in this thread. No matter, his attitude towards scanned or digitally created images will certainly not last too much longer. It is nice to imagine oneself a purist, but there is no such thing as a perfect rendition of reality in any form of photography. Ansel Adams is a great example of someone who made that evidently clear with his comment that a great photograph is made, not just taken.
As newcomer to medium format photography, and someone on a tight budget, I find that I can produce very nice images by scanning my 645 slides with my Epson 2450 scanner. The scans are almost never perfect renditions of what is on the slide, and some digital post processing is almost always required. But I like the ability to control that process myself, instead of having to pay someone else to scan and print, or to optically print my images. It is far less expensive, and because I care more, I think I can produce better images compared to some anonymous person in a lab who is working against the clock.
The website of Bruce Dale is worth perusing: brucedale.com