That is part of the beauty of "Star Trek", it's the rare film that reinvents the franchise without negating the franchise's previous history. The film uses time travel to turn this movie into a sequel/prequel/reboot of the previous films. Leonard Nimoy is brought in as a nod to the previous "Star Trek" films and spin-offs and is used to hand off the torch to the new crew of the U.S.S. Enterprise (similar to how William Shatner passed the tourch to Patrick Stewart in "Star Trek: Generations").
The success of this film is largely due to the cast and the director. Chris Pine, Zachary Quinto, Karl Urban, and Anton Yelchin all nail their parts while adding new aspects to their characters. Simon Pegg, Zoe Saldana, John Cho, and Bruce Greenwood also did well in their parts although their characters were not as close to the source material as the other characters were (which isn't their fault). Overall, I would say that the acting was excellent and one of the best aspects of the film.
The film also had a great style and stunning visual effects. This is due to the amazing job J.J. Abrams did on the film. Abrams made this film part old school "Star Trek" and part "Star Wars" and for the most part, it worked beautifully. "Star Trek" could not have been in better hands.
While the film was great for the most part, it did have a few flaws (like any film). I felt that the Uhura character was changed a little too much in the film. I also did not like the relationship between her and Spock. Spock in the original series always tried to distance himself from his human roots. A relationship with any human would be deemed illogical by Spock. It would have made more sense to have Kirk romance Uhura because the two always had a closer bond in the original television show (the characters shared the first interracial kiss on television) than Spock and Uhura had. It is a movie though, so some things can be overlooked for the sake of a good time.
I did feel like the villain of the film was a bit weak as well. Nero wasn't a bad character, but to really understand him and his quest for revenge, you had to read the comic book series "Star Trek: Countdown" which led to the opening of the film. Without the comic book's background information, Nero seemed very one dimensional.
I also felt that some of the deleted scenes (such as Nero and his ship being captured by the Klingons) should have remained in the film because it would have helped aspects of the story make more sense. Without that little subplot, it just seemed like Nero disappeared for twenty something years till Kirk and Spock were old enough to handle him in a fight. I also felt that from time to time, the humor of the film was overdone. Kirk with swollen hands and tongue was a little much.
Overall, I felt it was an excellent film with a few imperfections but well worth the journey.
OVERALL GRADE: 9/10