Loved it!
** Into Darkness Spoilers Ahead **
OK, I am a Trekkie, and I loved the new movie! I am a huge Kahn fan, and I still loved it. I agree with Aravis K that they should have made Kahn an Indian/Sikh like he was supposed to be ToS, but the actor they had playing Kahn was very good even though he was Caucasian. (Just as latino Ricardo Montalban was a great Kahn in Space Seed and Wrath of Kahn.)
I just love this new time-line, so we can have the old characters on new adventures. To me it is a great way to refresh the series, so I had no heartache with this re-imagining of what might happen with Kahn in this new more frightened Federation.
I am really loving the new actors, and Quinto (is that right?) as Spock was a standout; this was really his time to shine, and he did. (The actor is an outspoken Christian btw.) The switcheroo scene where Kirk has sacrificed himself to save the ship from Kahn, and Spock was on the other side of the glass -- I can't tell you how I loved that! I have seen "Wrath of Kahn" about a billion times, and seeing how they reversed the action and preserved some of the dialog ... it was beautiful. I was in tears. And Spock's shocking "Kaaaaaaahhhhnnnn!" moment was wonderful. Campy, funny, and just right, IMHO.
His fight with Kahn on those flying machines over the city was wonderful, and when he finally grabbed that piece of metal out of the side of the machine to brain Kahn with it -- totally reminscent of how Kirk defeated him in the engine room in ToS by whaling on him with what appeared to be a piece of PVC pipe he pulled out of the wall. I loved it. Of course, having Uhura there was a nice touch, too. I like that romance.
If other Trekkies think this is just a rip-off of Wrath of Kahn, that's one way of looking at it, but to me it was an homage to Wrath, a reinterpretation of how that story might go down in a new time-line where whole worlds (like Vulcan) have been wiped out by an unknown enemy, where there's more fear and less peace ... I found the whole thing brilliant.
**End Spoilers**
There was a good bit of violence but nothing graphic, and the language was minimal. I would see it again.