While Air Transat expand from Dublin, there is still a huge demand, both inward and outbound from Northern Ireland to Canada. Zoom, while it came so a sorry end, showed just how much demand (potentially very price sensitive) there was with year round Toronto, Vancouver and a limited Halifax programme. Belfast has had a Canadian link for probably appraoching 20 years or more, with Air Canada operating 747, 767 and L1011's in the past, along with a whole string of different carriers.
Like Zoom, Globespan and Skyservice came to a sorry end, although with Globespan the tour operator, rather than the airline, operated from Belfast for many successful years using Air Transat with multiple flights per week.
While a scheduled service would be excellent, and hopefully EI may consider in the future, what we need in the short term is to get a consolidator or tour operator, like Canadian Affair or American Holidays, to restart this route.