The special effects in this movie were simply incredible, and in IMAX they are larger than life. The acting was decent, there was good humor (for fans and non-fans alike) and there were subtle (including some not-so-subtle-at-all) throw backs for die hard fans to enjoy.
Chris Pine's rendition of a young Dr. McCoy was so dead-on it was border line creepy, and Simon Pegg's Scotty is priceless.
I predict more sequals, due to the clever time-line "alteration" in the script.