Good Lord, guys. . . RotK was already 3 1/2 hours long in the theatrical version. Looking at all the added scenes in TT Extended Edition, you don't think it's possible that they may add in most of the stuff you all are talking about? Between the movie and book, they had a LOT of ground to cover in RotK, Shelob was in TT book but halfway through RotK, I'm sure they had to chop off a majority of the storylines and backgrounds. I could definitely tell, especially in the beginning of RotK that scenes had been deleted, it cut from one scene to the next so quickly.
Granted, I'm not a "purist" by any means, but I am a fan of the movies. Recently, making movies based on books has been major let downs (see Micheal Crichton's Congo, Sphere, Lost World, the list goes on and on) but I'm impressed with this trilogy. C'mon, they shot all three movies at the SAME TIME; without ever knowing if the first was going to be a success! That in itself is incredible to me.
Honestly, you can't please everyone, but if I made a movie on a book, I'd be more concerned about pleasing the general public with it's entertainment value than worry about the storyline and history for the purist who make up a whopping .01% of the general population. IMO