I saw the play last night. Really didn't know too much about it going in - thought it was good, but not excellent (granted, it was the third performance of the run). I second the comment about Amanda Plummer and Bill Heck's performances, particularly Heck. The set looks great, and there's one particular effect which was fantastic!
I was a bit perplexed by the character of Maxine - I'm not sure if it's an issue with Dana Delany herself, but perhaps someone more familiar with the play can set me straight. The costume as well as the way she acted (again, not sure if this was Delany's choice or the director's) just felt out of place for 1940.
It was great to see James Earl Jones on stage, even though the role is relatively minor in terms of stage time. He was wearing what appeared to be an earpiece, but if that is indeed what it was, it didn't have an impact on his performance whatsoever - no awkward pauses or dropped lines.
I know there's a strong trend of ART productions transferring to Broadway lately, but I'm not so sure about this one. The cast is solid and by the end of the run it will surely be improved, but I feel like it might have a hard time finding a venue or audience in a pretty crowded season. I suppose it could fit somewhere like the Belasco or Friedman (if that's even possible given their relationship with MTC). Frankly, I would prefer to see the Huntington Theatre production of A Confederacy of Dunces on Broadway (especially if Nick Offerman reprised his role), but I think that ship has sailed given it's been more than a year since it closed.