Fair warning, this has spoilers!
Into Darkness was an enjoyable theater experience, something that JJ Abrams has delivered twice in a row, a rare feat for Star Trek movies. Although his movies sometimes feel more like Star Wars, seeing good Trek on a big stage making millions of dollars is a good thing.
Let's start with the things I liked: (1) I liked the symmetry of the story, seeing Khan use his own blood to save a girl and start his plot against the Federation leaders at the beginning then seeing the Enterprise crew do the same to save Kirk at the end, (2) Cumberbatch was good, but the glowing praise for Benedict Cumberbatch seems a bit much...he was
great compared to Eric Bana's Nero, but that's like competing against a
cardboard cutout. I felt like Cumberbatch was outshined in the bad guy
department by Peter Weller's Admiral Marcus, and Weller was incredible, (3) The visuals were stunning, especially the redone warp departure, and the Enterprise felt like much more of an important piece of the story this time around, (4) I loved the return of suspense to the Klingon relationship after decades of post-TOS stories made the Klingons friends, (5) Almost each character in the ensemble crew had a memorable and significant role, much more so than the 2009 Trek.
There were a few things I did not like also: (1) Did we need another Prime Directive story to start off?, (2) Why do we insist on going back to Earth again, there was little reason to stage much of the ending there, (3) I'm not a massive fan of the flipped Wrath of Khan redone ending, good for nostalgia only but lost the emotional punch of the same scene in Wrath of Khan, (4) Not a fan of Carol Marcus so far, but that was one of few weak points in the character development, (5) the Klingon fight scene on Kronos felt like a rejected scene from Mortal Kombat.
Bottom line: I had fun, but for some reason the movie left less of a positive overall impression than 2009 Trek. I give it 4 out of 5 stars. However, I love that the beginning of the 5-year mission ended the movie, as that hopefully means a new fresh story far away from home in the next movie or even better, a new television series.