In terms of the quality of the film as a whole, I would give Doctor Strange a 7, but because of its visual effects and implications for the Marvel Cinematic Universe, I am totally giving it an 8. Let me explain.
Watching this in theaters with the sometimes too-loud sound, seeing the buildings and streets give way and rotate and otherwise bend themselves completely to a person's whim, immediately made me think of Inception. But this was even more hectic. This wasn't imaginary, this was real.
Another thing. Finally in the MCU we have some sorcery, direct utilization of magical energy for combat. Discussion of other dimensions; even traveling between them at will. Doctor Strange's final outfit is just wicked cool. If you know the character from the Marvel comics, then you'll know that he's pretty damn powerful. Unfortunately this is an origins film, that is, it reveals how Doctor Strange became Doctor Strange the Sorcerer Supreme; the real deal will come in the third Avengers film hopefully.
As a follower of the MCU who's seen basically all of the released films to date, I was eagerly awaiting this one, and I was not dissatisfied. The music was riveting as usual per a Marvel film (Giacchino), the fight sequences intense, the otherworldly conflicts enormous. I'm so glad this guy's joining the Avengers in their imminent battle with Thanos, or at least I'm pretty sure he is. Now all that being said, Doctor Strange wouldn't fall in my top 5 MCU films; Captain America, Avengers 2, for example were much better, but it's part of the MCU, and therefore is a must-see for any MCU fan.
I also noticed a lot more wit and almost off-character humor in this film than in other MCU films. And of course, as all the MCU films are taking place chronologically within the same universe (or multiverse?), there are several references to the bigger pictures, i.e. the Avengers.