The latest issue of Empire Magazine has an interesting remark by Marvel Studios president and producer Kevin Feige.
He says that Doctor Strange is the doorway to Marvel's supernatural universe.
There’s a whole other side to the Marvel universe, which is the supernatural side. We’ve always been very interested in this aspect and this is going back to the early days of Strange Tales with Steve Ditko and Stan Lee. I love that stuff. We haven’t done anything that mind-trippy yet and for me, Doctor Strange is our doorway into that.
Perhaps what Feige means is that once the door is opened, there is more to come. Hopefully if Doctor Strange is a success, we could get other Marvel Comics supernatural characters eventually. Of course, there is most likely sure to be supernatural characters present in the Doctor Strange movie.
Stephen Strange was first mentioned as being a part of the Marvel Studios Universe in Captain America 2 when Hydra Agent Stillwell let it be known Stephen Strange was a target.
Marvel has yet to officially announce a Doctor Strange movie, but it's thought the reveal could be coming this Summer at Comic-Con as part of their Phase 3 plans.