Ryan I think its more cork and knock who need to watch out. Can't see any carrier from Dublin moving to SNN for lower charges as long term it will hit there yield in an established market at DUB.
THe only real danger for ORK and NOC is will Ryanair go back into SNN and take all the current NOC and ORK routes that were at SNN back. I see no other airline going to switch and I don't think it will have a huge inpact besides FR.