United States

Getting there:
Flight's don't come cheap to the US.If you book far in advance you are talking between 600-750 return to all the major East Coast airports. Depending on what University you are going to, getting there on public transport may be difficult due to Americans not liking trains/buses. Best bet would be to send an e-mail to your university's exchange co-coordinator to see if they can help you out. Every US college will have one.

Undergrad/Grad-school divide.
So depending on what you are studying in Trinity you will be heading over to either an undergrad school or a grad school. The two experiences are completely different. For all law students you will be heading to graduate schools. Everyone is minimum 3 years older (with a lot of them being a lot older) and they are a lot more focused on academics than the undergrads. Many of them will spend every day of their time studying, often neglecting to live as human beings. Don't let them put you off, the work will be intense but with graft it is very manageable and rewarding. The standard of teaching here in W and L is brilliant, I've heard similar stories from my friends in Emory and Indiana. I've been able to study topics I can't do at home which has been great.

Cost of living:
America is generally cheaper for most stuff than our emerald Isle. Most places have a wal mart/kroger and if you're willing to ignore your inner moral qualms and shop there you can get literally anything you can think of under one roof for cheap prices. The beauty of unchecked capitalism eh?

Socializing:
Strictly enforced 21 drinking age and aggressive cops. Nuff said.

Exams:
Most exams over here are graded to a B+ average which translates to 67 back home (at least in the law school) so that's quite handy. As I have said the work is intense but is manageable.

Americans:
Fantastic people, they love their freedom and you will too.