Aer Lingus were planning to cut Shannon-JFK, but before they announced it, Delta announced that they were pulling off the route. That should enable Aer Lingus to keep loads and yields up.
There is a market for Shannon-New York, so I'd say it should survive, although frequency cuts are possible. As a route, it may have been more suited to one of Delta's 757s than Aer Lingus' A330s.