This is some way in the future but I like to be prepared....
I am a Swiss citizen by birth and lived there until I was 17- I am now 33. I then came to Ireland to learn English, but remained here first to study and then work (all legally). I became an Irish citizen in due time (in the year 2000) and now hold dual citizenship, Swiss and Irish. Then I met my American husband, who came over here to get married to me, and am expecting twins by him, who will become US citizens as soon as they are born here in Ireland (well, soon after- I know the process for that and it is so much easier than my path to US citizenship!). We are planning to do a DCF and move to the USA sometime next year. I would rather not give up either of my current citizenships, even when I get US citizenship in a few years, but I know that the USA, while tolerating dual citizenships, isn't fond of them. I have no problems with most of the oath of allegiance, and totally accept that I will be under US law and owe that country allegiance while I am there. However, maybe when we are old and retired we might want to move back to Ireland and frankly, while I look forward to living in the USA, I think if, G_d forbid, something happened to my husband I'd want to come back to Europe.
So my question is: will I be allowed to hold triple citizenship, or will I be asked to give one/ both my European citizenships up when I take the test to become a US citizen? Might they ask me even earlier, at the DCF interview, what my intentions are that way? Both Switzerland and Ireland have no issues with holing multiple citizenships, so there is no problems from those countries point of view.