They are as noted prototype devices – with no announced release date – so it's completely in the realm of possibility that the camera simply isn't ready yet. Of course that doesn't excuse the misleading video and pictures Nokia used to advertise it.
I was actually wondering about this, maybe you can enlighten us.
Could they not have used external ligthing for the Nokia shot, and none for the competitor shot? How do we know they used the same lighting conditions?
Not trying to feed the anti-Nokia, I've always been curious of these types of things.
http://www.theregister.co.uk/2012/09/05/handson_nokia_lumia_...
"Alas, the Minders leapt into Red Alert mode to prevent me transmitting the results, you'll have to take my word for it."