Meh, 99% of trilogies are MUCH worse by the final film and to a degree LOTR was no exception, the third film being massively weaker than the last few films.
The Hobbit part one, frankly only reminded me of The Phantom Menace, compared to LOTR it was god damned woeful, as a stand alone film it was passable but really quite poor. The jokes misplaced as others said, trying to make it more modern is a massive massive mistake, the horrendous CGI forced in to make more "hollywood" style action that stupid audiences want. Very few parts of the film generated any tension at all, each and every battle was predicatable, telegraphed every single change of directoin in a battle, the now massively overused identical music which is becoming comical in its use and also telegraphs every single part of the film.
Why didn't Peter Jackson want to direct this movie initially?
Peter Jackson previously signed on as an executive producer (the same role that, comparatively, George Lucas served on Episodes 5 and 6 of Star Wars); The main reasoning appeared to be timetable conflicts with other directing commitments Jackson already had or has made (The Lovely Bones, Tintin). The fact that Jackson was in a financial conflict with New Line Cinema at the time may have also played a role. There may also be the matter that the previous Lord of the Rings movies are hugely popular movies. This will raise the expectations for The Hobbit considerably, while the novel is in many regards (e.g. story structure) quite similar to the Ring-trilogy, which has also become much more popular than the Hobbit over the years. With Peter Jackson at the helm, expectations will likely rise to unrealistic proportions. This could lead to potential mass disappointment with the fan base, arguably comparable to when George Lucas decided to create his prequel trilogy to the original Star Wars trilogy himself, and when Steven Spielberg created a fourth Indiana Jones movie after nearly twenty years. Jackson himself also experienced first-hand how high expectations can get when he is listed as director, having met with some harsh criticism for his post-LotR movies (King Kong, The Lovely Bones).
This kind of thing is what makes me think it will be poo, directors think "zomg, they loved the last one, the audience will expect bigger and better, I better do that", and then make a stinker of a film, trying to do to much. Which is why each and every film has gotten "bigger", but also worse, and trying to induce more excitement with more unrealistic crap and more CGI. Like bird from Lost being in it, not for the story, but because he wants to put in more names, put in a potential love interest, put in a pretty face, not because the story needs or should have it, but because he thinks he has to do more.
I'll be surprised if the next film isn't worse than this one, I'll be shocked if its actually a good film, and might have a heart attack if its anywhere near as good as LOTR 1.