On the 22 September 2015, the Northern Ireland Ordinance Survey (OSNI) which is now part of the Land and Property Services (LPS) released the OSNI Largescale Boundaries - Townlands dataset for Northern Ireland under a UK Open Government Licence

This comes 15 days AFTER OpenStreetMap user Stephen_Co_Antrim completed Syunshin, the last townland to be mapped in Northern Ireland!

Sorry OSNI, we beat you to it :o)