As a US citizen resident abroad you are required to file a US tax return each year regardless of wheather or not taxes are due! If your income exceeds the threshold you will be required to pay US taxes in addition to any Irish taxes you pay. The only way to avoid this and the new US tax provisions is to renounce your US citizenship at the US embassy in Dublin (they even have a little ceremony for it!).
Yeah, I heard about having to file whether or not I owe anything....and giving all details of all fin. accounts that you hold etc. Its very intrusive. I want to hold on to the citizenship for a while though. It might come in handy yet!
So, if I pay taxes in Ireland, do I just report those to Uncle Sam?