Just watched the extended edition this weekend, and it was just awesome!
I loved the additions to Faramir's character. The background with him, Boromir, and Denethor at Osgiliath were fantastic, and I wish they had included them in the original version. I told so much more, and gave me a reason to like Faramir, and understand his conflict. I agree now that having Faramir just blow off the ring would cut the throat of the movie. Why would a ring so powerful that it can tempt Gandalf and Galadriel suddenly be unable to tempt an honorable man like Faramir? Great additions!
I also liked the extended scenes with Aragorn and Eowyn. Not only did it give a lot more background on Aragorn, but it also expanded Eowyn's role to the point that her sudden crush on Aragorn doesn't seem such a contrivance anymore. Good work!
I didn't think the Isengard dam scene was bad at all. Maybe I'm not looking hard enough, but the scene looked great to me.
A couple of nits to pick and this just pertains to the movie in general (either version):
Legolas leaping on the horse...good. Noticeable CGI, but you have to look for it. And it was cool. Legolas surfing down the stairs with heroic music rising in the background....bad. So bad. Probably seemed a good idea at the time.
Too many speeches. Too much "We need to do this because it affects all of us!" The slow build to the battle at Helm's Deep, complete with slow motion shots of kids getting ready for war.
"Ride out and meet them."
"Frodo wouldn't have gotten far if it weren't for Sam."
"Because there's still some good in this world!" (Sad little Gollum looks down).
Ick. Ack. Yuck. I think Jackson was going for too many forced "moments" in The Two Towers, to the point that it weighed on the movie.
And if Pippin hadn't figure out by now why fighting Sauron was necessary....I mean, c'mon. Silly, silly, silly and all so Merry could have a dramatic moment. Blech.