Mr. Jackson does like his dwarf jokes, no?
Saw it today at 8pm; my initial impressions:
1) The opening scene is utterly wonderful, as is the battle on Zirakzigil.
2) Not enough time spent developing the ents and their response to Saruman. I would have preferred less of the Battle of Helm's Deep and more Treebeard/Merry/Pippin dialogue.
3) Personally, I found Faramir a bit overly unsympathetic. I'd have preferred a greater development in Frodo's and Sam's relationship with him from severe mistrust to respect.
4) Gollum is just magnificent. Well acted, wonderfully scripted, and the CGI isn't bad either.
5) Theoden's transformation from withered shell to active leader is a bit too severe, IMHO. I'd have preferred a more subtle change, and for Bernard Lewis to have been made up to look a bit older even after being cleansed of Saruman's influence.
6) The film's structure varies WIDELY from that of the book. Personally, I think the film was very well structured, and that the filmmakers made excellent decisions vis-a-vis elimination of certain portions of the book and re-ordering of certain other portions.
Overall, I have to say that I liked this one less than Fellowship. It's got great action scenes, but IMHO less mythic complexity, dramatic development, and power than FotR. Much of this is the fault of the book, which as a middle book must have been more difficult to conceive and implement as a film. But in general, this one has fewer "soft" bits than FotR, and since I tend to think that FotR handled the soft bits well, I miss them here. Also, the filming style here is much more heavy-handed (dramatic lighting and LOTS of slow-mo). There is some cinematic imagination at work (notably the beginning and a crazily-transforming dream sequence in the middle) but less than in FotR, IMHO. Not to say that The Two Towers isn't GREAT, but I don't think it's quite the equal of Fellowship.
Oh, and Eowyn's character is developed with incredible sensitivity and pathos. She's acted well too.