New Official Irish Standard
Great news: simplification of some grammatical rules, regarding numbers, initial letter changes. This standard is defining the rules of the artificial "Córas Lárnach", a standardized Irish to make it possible to learn it and agree on official rules without having to be born in the family of the ones making the rules.
Main changes: - Counting will become simpler over 20. - The úru will be allowed after sa and den. (Standard remains the Séimhiú though)
Of course you can still stick with the older official rules, or the regional variations. It simply means that for the exams, students will not be penalized as much for not knowing complex rules that may have lost their appeal.
Download the new version: http://www.oireachtas.ie/parliament/media/translators/An-Caighde%C3%A1n-Oifigi%C3%BAil_2016.pdf (In Irish, as it should be...)