Saw it a few weeks ago. I'm a casual Coens fan - loved Raising Arizona, Fargo and Miller's Crossing, but nothing else has really grabbed me.
Just had to qualify that I thought Serious Man was incredibly boring and depressing. I see what they were trying to do and there were some uncomfortable chuckles from me, but ultimately it was just too unpleasant. However there were some huge guffaws from other audience members. Maybe you have to be Jewish to really get the full impact?