Part one, Wave of Irish immigration to Boston begins to slow, describes how fewer people emigrate from Ireland to the US (and specifically to the Boston area) in a post-9/11 world of security worries and hostility to immigrants in general. Part two, Ireland's prosperity has many reversing their exodus, tells the tales of those who've gone back from Boston to the Emerald Isle.
I'd known that the Irish economy was taking off, and figured that might tend to cut down on economic migration from Ireland to the US. I was surprised, though, not only that there was still such a large informal / illegal population in Boston, but that the general immigration crackdowns were hitting that community so hard. It's also a lot harder, apparently, to get the paperwork necessary for legally working in the US. Ireland's a member of the EU (thus Irish citizens can work anywhere in the EU as a matter of right), while other nations (such as Australia) are still welcoming Irish immigrants; small wonder, then, that there's less interest in coming to "the next parish over", as Boston used to be known.