Here's a nice seasonal (OK, a little early) work by a Northern Irish composer. Sean Doherty (born 1987) is also a member of the New Dublin Voices. He has won numerous prizes and is getting a good amount of performance. Interesting note: his Ph.D. dissertation was "Solfaing: A History of Four-Syllable Solmization to the Present Day." I'm sure this would be a treat to read for all the shape-note singers out there with a scholarly bent.