I really liked it and I too thought Julianne Nicholson was a highlight. SPOILERS THROUGHOUT
It was a mistake to cut Jean's monologue and her scene with Johnna. I thought it was more effective hearing the Barbara/Bill backstory from Jean, and we need the scene in order to create a bond between her and Johnna that will justify Johnna hitting Steve with a shovel. On stage I sensed keenly that Jean is the only Weston Johnna would go to bat for, as it were, since she is arguably the least insane and she pays the most attention to her (not to say that Johnna is that shallow.)
I felt like Meryl ran past some of Violet's most important lines. I remember both Estelle Parsons and, more emphatically, Phylicia Rashad giving especial weight to the line, "But I would have waited anyway" when telling Barbara about the note Beverley left. The audience in the Music Box gasped at that, and while it was a very vocal audience in the movie theatre today no one reacted to the line in the film.
The directing was pretty solid. I see now what Wells was talking about when he defended his decision not to cast Kathy Bates as Mattie Fae because she doesn't look anything like Streep. I felt that all the Weston ladies looked remarkably alike in the movie, specifically in their noses. And all of them except Mattie Fae and Karen bite their nails - most notably Barbara and Jean, and then Violet starts doing it later on. I may be reading too much into it, but I think it's significant that Violet spends a lot of the film in sunglasses and then in Jean's final scene, right before she rolls up the car window to block Barbara out, she is wearing sunglasses. Maybe a coincidence, but I see it as one of the moments when I felt like Wells drifted from what Tracy Letts was going for. In the play Jean is very clearly her own person, and her greatest hope is in not turning out like her mother and grandmother. Jean on film is a little bit more vague, largely because her monologue has been cut, and it doesn't help that the last time we see her she is costumed in a way that links her to Violet, le grande fvckup.
Also on a directing note, the new ending feels extraneous. I don't know if I just feel that way because it is the most significant way in which the film deviates from the play. I was very, very worried that it would end with Barbara making a U turn and going back to her mother - not just because that doesn't happen in the play, but because it would invalidate Violet's abandonment. I was relieved that doesn't happen, but then the very last shot shows Barbara driving toward Denver. I know Letts wrote the screenplay and so he would not have Barbara going back to Jean and Bill if that was not where he intended her to go at the end of the play anyway, but I preferred when it was little bit more ambiguous.
I know you.
I know you.
I know you.