I've really liked Hughie since seeing the '80s TV version with Jason Robards, who I seem to remember emphasizing the anger, abrasiveness, and despair of the main character, Erie Smith.
Since then, I've seen the show live a number of times. Al Pacino was very funny and endearing (a lighter version of the low-level hood that he played in Donnie Brasco around the same time). Richard Schiff a few years back really captured the character's hangdog loss of confidence. And Brian Dennehy conveyed the sense of a once powerful character now on his last legs and at the very end of his rope.
As for today's performance -- I found it well worth the time, effort, and $37.25 I spent on my orchestra seat. I thought Whitaker captured at least as well as any of the above-named actors the huge sense of loss that Erie feels at Hughie's passing. Unfortunately, probably the most moving part of the play, where Erie expresses those feelings most directly, was badly marred by somebody's alarm beeping for what seemed like a good 10 or 15 seconds.
As for Whitaker's performance overall, I found it mixed -- sometimes excellent and never bad, but it did seem that he still had to focus too much on just getting the words out accurately. In fact -- and this is just an impression I got, which may or may not be correct -- I think Whitaker did again use the water cooler to receive a line, and I also wondered if he may have had prompts written on his racing form, racing tickets, etc. In any event, those items seemed to come into play in this performance much more than I remember them in any of the other versions I've seen.
On a different note, at least from my orchestra seat I liked how the partially blocked, big green HOTEL sign suggested the word HEL(L). I don't know if that was on purpose, but it was very effective, I thought.