As a jumped up Norwegian (you've clearly never met a norwegian) resident in the isles I can confirm the story, whether it takes off or not is another matter. If they've any sense they'll use Scatsta instead of Sumburgh to keep the costs down. As for the critisism of BRA - they certainly deserve some of it - £280 return fare for a 50 minute flight, I've spent quite a few hours in Aberdeen waiting for BRA to get the plane off the ground, and not all of it tech problems either, e.g. deciding whether to offload fuel or passengers as they've realised they've exceeded their weight capacity, waiting 30 mins for 5 inbound aircraft so they could use the longer runway - weight restrictions again, I could go on.
I'm sure someone could\will eventually offer some competition to BRA.