The expected one million more passengers should translate into approximately 1,000 new jobs.
More than one hundred jobs were created immediately: 75 cabin crew, 25 pilots and 10 ground crew.
Four years ago there was only one nternational flight into Belfast International Airport.
Now there are 30 and Aer Lingus will bring eight more.
Up to 1.5 million passengers head south to fly from Dublin each year.
The new routes should mean around 500,000 of them flying from Northern Ireland instead.
The reaction from the Shannon region to the loss to Belfast of the Heathrow flights has been little short of hysterical, with much of the sentiment distinctly partitionist.
One can hardly imagine Gordon Brown coming under a great deal of pressure or it taking up a large part of his day if a Scottish or Welsh airport was similarly losing a connection.
In the frenzied atmosphere in the west of Ireland, one Government Minister described it as an 'Armageddon' situation.
Undeniably there are implications for that region.
Tourist projects including development of a golf resort have been put on hold, but much of the threat is exaggerated.
Almost half of companies in the region questioned in an Ibec survey thought the impact on their ability to transfer freight abroad would be reduced, but Shannon hasn't provided short-haul freight flights for many years.
Shannon will still fly to more than 50 destinations including all the other London airports and seven transatlantic routes.
Vested interests and local lobby groups retain excessive influence.
At masses and church services in the west of Ireland, churchmen spoke of the 'moral obligations' of reversing the Aer Lingus decision.
Shannon's immediate catchment area in Clare and Limerick is less than 300,000, compared with close to 1.8 million people in Northern Ireland and more in counties just across the border.
Aer Lingus have clearly calculated that they will earn more from flying from Belfast.
Part of the attraction is undoubtedly that this is a different jurisdiction with its own employment laws, pay levels and grants system.
Costs will be lower and with the local economy doing well the potential for growth is greater.
Aer Lingus was in dire financial straits in the early Nineties and then again after the September 11 attacks.
They underwent major restructuring, reduced their cost base, cut jobs and axed marginally profitable routes, transforming from a struggling national carrier to a successful low-cost operator.
When Bertie Ahern and his Cabinet meet to discuss this issue, they are not assisted by comments they have made previously. Former Minister for Transport, Martin Cullen, while presiding over the privatisation gave specific guarantees.
He stated that the Shannon-Heathrow flights were "critical to ensuring connectivity" and that "the Minister for Finance as a shareholder in the company acting on the advice of the Minister for Transport is unlikely to support a proposed disposal of any slot… and is likely to require the convening of an extraordinary general meeting".
In March 2006, Aer Lingus chief executive, Dermot Mannion, accepted the right of the Government to intervene in the company's affairs, saying, "the Government will go in with a significant shareholding, which will give them the opportunity to block matters for strategic national interest".
However, it would be entirely inappropriate for the Irish Government to seek to meddle. Intervention on their part would be subject to legal challenge.
Furthermore it would dissuade potential investors from overseas, as well as undermining Mannion utterly and making his position completely untenable.
The Northern Ireland economy is not the only winner in the Shannon debacle. Michael O'Leary of Ryanair hasn't had a bad few weeks. He has increased his stake in Aer Lingus to 28 per cent and summoned an Extraordinary General Meeting to embarrass Ahern and his Government colleagues particularly from the west.
Ahern will desperately want to avoid an EGM and is likely to attempt to cobble together a compromise involving a reduced number of Heathrow slots.
Aer Lingus choosing Belfast was great news for business and travellers alike.
Having three aircraft permanently based here is a sign of their commitment to Northern Ireland and their belief in the province's potential.
The new routes will be enormously important not only in developing business links but in the growth of tourism here.
The travelling public will also benefit from these new routes, not just through increased choice of destination, but with competition on some of the routes it should lead to lower fares for passengers.
There is also greater future potential.
In particular, the possibility of new transatlantic routes from Belfast would allow Northern Ireland to capitalise further on the huge market within the United States which is still relatively underdeveloped.
Tourism has the potential to improve our economy significantly. Eighty per cent of tourists to the island of Ireland currently don't venture into Northern Ireland.
It is a positive development that Northern Ireland has been designated Approved Destination Status for Chinese visitors. This makes it easier for them to obtain visas to travel to such destinations.
The World Trade Organisation predicts that by 2020, 100 million Chinese will be holidaying overseas. Any advantage Northern Ireland can acquire in tapping into that market will be potential lucrative.