When I first saw The Hobbit: The Desolation of Smaug it was a late showing (10 or 10:30PM). And, while I normally have no problem watching a movie at that hour, in this case, my body pretty much shut down, and my eyes closed for a few scenes. I also saw the film in the high-frame-rate 3D presentation. The fact that all the characters looked "real" and the whole thing felt like a live BBC production (thanks, Mike, for that completely accurate description) also distracted me tremendously. So, while I enjoyed the movie, I don't think I got the experience I was hoping to get.
Well, I saw the film again. That's right, I decided to see a three hour movie that I thought was solid a second time. I'm crazy that way. But this time was an earlier viewing and in 2D. What a difference it made. I really enjoyed the film. The things I liked about the film the first time I saw it were even better. I also found that I could concentrate on the film itself rather than the faces of the actors (which I could not look away from in the high frame rate version).
I still have a problem with the last quarter of the film, as the movie bounces back and forth between Smaug and Bard. I think it slows the pacing down when all we want to see are a hobbit and dwarves fighting a dragon. However, Evangeline Lilly's Tauriel is still a fantastic creation. Maybe the romantic triangle between her, Legolas, and Kili the dwarf is a little contrived, but her actions are amazing. She's the once character who gets to grow and develop throughout the film.
But I may just be happy because any film that has giant man-eating spiders in it is okay in my book.