Thomas Demand's Space Simulator part of his exhibition at IMMA until June. A really good show that is much more engaging then you'd think. Includes some of the most gorgeous photographic prints I've seen and a brilliant specially designed (by Caruso St. John Architects) installation/viewer for his Rolltreppe (Escalator) film. I'd have photographed it but IMMA forbids photography and of course doesn't have a pic of it on their website even though it's a Dublin first, go figure. Highly recommended.
Also at IMMA is a major Alex Katz exhibition which really left me cold, I know people like him but I don't get it.