One good thing about the 'No' vote is that we can wait to see how the wind blows in the US election. If we have a second Lisbon Treaty next spring we'll have had enough time to see if President Obama's protectionist policy proposals look like a runner. If they do, then a 'No' vote would be all the more costly as the world's big blocks start throwing up the shutters. It would be foolish to remain outside the EU in such circumstances (unless Ireland is offered some alternative membership in NAFTA). If, however, the protectionist noises fade away after the election then the dangers of being on the outside of the EU would be lessened.
A mid-April re-run of the Lisbon vote should be late enough to know where things are going.