Obama visited Ireland in 2011. I remember the Clinton visit in the '90s. Both shut the city down and increased the presence of security forces everywhere. I worked in the city centre at the time and it was chaos for a few days.
Making matters worse was the fact that a week or two prior the Queen visited (arguably a more important state visit, for historical reasons). So in effect, for about three weeks, Dublin was hell to commute in.
As someone else pointed out, their revenue is pretty decent. But their biggest asset is likely key staff as well as, as social networks go, that it has the cleanest/most useful database of users.
Making matters worse was the fact that a week or two prior the Queen visited (arguably a more important state visit, for historical reasons). So in effect, for about three weeks, Dublin was hell to commute in.