When I walked out of Thor: The Dark World, I asked a friend what he thought. His answer, "well... that was a movie." I laughed, but come to think of it, that about sums up how I felt.
Looking back on my thoughts for the first Thor film, I think I was just more surprised with what Kenneth Branagh and co. were able to get right as opposed to looking for things that bothered me. I always felt Thor would be the most difficult character to capture on screen. Do you just make it a PG-13 version of 300 and feature Thor and his viking comrades? Do you show Donald Blake walk into a cave with a stick and then suddenly turn into a superhero? Since Marvel Studios was planning for Thor, Iron Man, the Hulk, and Captain America to be part of an Avengers film, the idea of focusing on both Asgard and Earth actually led to the first Thor being an enjoyable fantasy-action movie.
This sequel, feels quite similar to the first. There's some action with the sensibility of your average video game, but the characters and performances (especially in concerns to Chris Hemsworth, Tom Hiddleston, and the chemistry between the two of them) keep everything moving. Only in retrospect did I realize how the film plodded along and how forgettable it all actually is because at the time of the movie I was too busy saying "oh, that's kind of cool" (I think it helps that I am such a die-hard comic book fan).
Back to the reaction of 'oh, just another movie'... this unfortunately just feels like another placeholder for Avengers 2 similar to how Iron Man 3 wavered between being its own singular adventure and still being a part of a larger universe. I'm curious as to when Marvel will decide to return to the world of Thor because there are some interesting plot threads left open, but sadly it seems we'll have to wait until 2016 at the latest.