How are American students generally accepted at TCD by other students and/or faculty members? Do American students seem to have a difficult time assimilating into TCD student life or into Irish culture in general?
1. TCD is a leading university. They're used to international students. I felt welcome as part of the student body--and I was only there as a visiting student!
2. I'm pretty sure the only Americans to have a difficult time assimilating are those who choose to isolate themselves by only hanging out with other Americans or whatnot. I can't really speak to this because I spent most of my time with Irish/European students. Get involved with student societies. Be friendly to your classmates. etc.
3. Americans who try to be to Irish are annoying. Don't assume all of Ireland is "quaint" and remember that if you happen to be of Irish ancestry that doesn't make you "Irish." Basically common sense: don't act like you expect all the Irish stereotypes to be true and don't act like a stereotypical annoying American.
4. Watch Father Ted. Seriously. It's a sitcom from the late 90s and, aside from being bloody hilarious, it has become a bit of a cultural touchstone. Most Irish people know it, so being able to recognize references to it might be good. Also, as I said, it's bloody wonderful. If you're really religious you might find it a little offensive, but other than that...anyway, I'm pretty sure it's on Hulu.
Caveate: I love Ireland and would rather be there than hear (I have periodic fantasies of completing my training in the US and then pulling up the stakes...). I also had taken numerous trips to Ireland as a kid, so I was already kind of knew what to expect. The reverse culture shock (that is, coming back to the US) was a lot harder to deal with than the culture shock of going there. My point is, I might not be a typical case. The only things I really missed when I was there were snow (I'm a cross-country skier), some of the particulars of life in New England, and being in the same time zone as my family.