Regional Google results

For generic terms the Google.ie "web search" results used to be dominated by "foreign" pages and you'd need to append "Ireland" to the search term to see any Irish results, thankfully that's no longer the case.

Most results now contain a mixture of Irish and "world" pages, with the appearance of Irish pages determined both by their competitive strength and the order in which they appear in the "pages from Ireland" results.
Same pattern goes for the "foreign" pages, and to date there is no indication that regional links will help them rank on national Googles.

Not all generic search results will show Irish pages, there seems to be a competitive line that needs crossing before an Irish page will feature, but once it does it can outrank some of the major world players.

The other crucial factor is inclusion in the "pages from Ireland" listings which "traditionally" meant a .ie domain or an Irish IP, though Google recently introduced geographical targeting to its webmaster tool set which may turn out to be a third way into the PFI listings for some.

While dealing specifically with G.ie, this holds true for all the English language regional Googles, "world" rankings for generic terms are going to become increasingly difficult to attain, particularly where there is any decent local competition.