Copied from my post on FB:
Watched Doctor Strange tonight. VERY good. A worthy addition to the Marvel Cinematic Universe. Well written and directed, and a truly incredible cast of actors. Also, some of the most insane, trippiest visual effects I have ever seen. I have no idea how they envisioned it in the first place, much less filmed it. If this movie doesn't get nominated for an Academy Award for visual effects, it will be a crime.
I must say that at first, it was a little odd hearing Benedict Cumberbatch speaking in an American accent. But he was great. Personally, I look forward to future Marvel films, where he can work opposite the established roster, like Robert Downey Jr. or Scarlet Johannson.
For the uber geeks like me : I was a tinge disappointed that Doctor Strange worked his spells without the incantations he used in the comics. However, that's a small concession to make for a film this good.
I would tend to agree with the opinion of Guardians of the Galaxy director James Gunn: if you have the opportunity, I recommend seeing it in IMAX 3D. But see it, by all means.
If you don't have access to IMAX, definitely see it in 3D, at least.
Oh, and the score is pretty good, unlike most Marvel films (what has big their one major flaw, IMHO).