The first Thor skated by mostly on charm - Chris Hemsworth & Tom Hiddleston's, specifically. After a steady uptick in the quality of the Marvel films, we were all hoping that Thor 2 could take some of the lessons learned from Cap/Avengers/Iron Man 3 and really go to work, giving the God of Thunder and his associates a cosmic-level crisis into which they could dig their teeth, underpinned by some better material for the characters we'd come to love.
Well, The Dark World definitely succeeds in raising the stakes, both in regards to danger, and the presentation of that danger, but it still feels more like we're seeing points checked off a list than an actual story unfold onscreen. Everything moves faster this time, but too fast for anything to leave much of an impact. When you have your bad guys played by actors as accomplished as Christopher Eccleston and Adewale Akinnuoye-Agbaje, you want them to savor their villainy, to be able to relish in their presence, but instead they glower in the darkness, with barely enough time to articulate their motivations, let alone craft characters.
But, really, we're not watching Thor for thoughtful musings on the nature of power, or good and evil, or the advent of a Darth Vader-ian bad guy, but for a pair of brothers, to see if their bond of family can really be severed by lies and betrayal. Every complaint about The Dark World fades away when Hemsworth and Hiddleston are onscreen - the film snaps to life when Thor and Loki stand together. The strength of the Marvel films has really been in their casting, and these two are some of the brightest shining lights in the sky.
Actually, the whole cast of humans & Asgardians is utilized darn well here - even Renee Russo, whom I'd honestly forgotten was even in the first Thor. All of our heroes, and their friends, get at least a moment to shine (usually in one of The Dark World's many spectacular action setpieces), and for us to remember why we liked them so much in the first film.
Marvel also keeps up their burgeoning tradition of quality extras on their home-media releases; the short film one-shot, "All Hail The King," is hilarious and thrilling. All in all, Thor: The Dark World is immensely satisfying, if still less than it could've been.