Apparently Marvel has recently met with Johnny Depp to discuss taking on the role of Dr. Strange according to Latino Review. While it's easy to dismiss such things, Latino Review has a good track record. They previously revealed Marvel was developing a Guardians of The Galaxy movie, plus Depp is already connected to Disney through the Pirates of the Caribbean series.
The role for Depp doesn't seem unreasonable either. He's known for playing wacky and weird characters so Dr. Strange could be a perfect fit. Of course even if he was met with Marvel, it doesn't mean he'll even take the role.
Dr. Strange is expected to release in 2016 so we'll likely have to wait until next year to find out more.