General Discussion

More advance than the second and forth hokage...

I'm not going to say it's more advanced so much as it is a variation of Kakashi's Kamui. Similar in concept and appearance, but vastly more powerful in application and apparently significantly less of a chakra drain. I'm fairly certain it's a fourth jutsu specific to the Mangekyo, since the only other person shown displaying anything on a similar level was, as mentioned, Kakashi's Kamui. However, it appears that only certain users of the Mangekyo can use it, as Itachi wasn't shown doing so, and I'd like to say he's considered the de facto master of the Mangekyo amongst the fanbase. So perhaps only those who have had the Mangekyo transferred into them can use that specific jutsu. Considering Tobi's apparent ability to transplant his dojutsu without harm or disabling himself, if his claim of the Rinnegan being his to begin with is accurate, this would not be entirely impossible.

@JonSmith said:

I'm fairly certain it's a fourth jutsu specific to the Mangekyo.

That's what I think. All of the MS jutsu that make sense to be eyes (ie not flaming skeletons or spitting fire) deal with the manipulation of space and time. Tsuyomi puts the user and victim in a place where they control time and space, Kamui sends objects and people to another dimension, and Tobi's does the same, but it lets him travel to the dimension and exit it wherever he wants to in the real world.

I don't know what Tobi's intangibility is though. It could be some MS technique since some of them have little to noting to do with optics or visuals.

@sickVisionz: I think it was said, or at least theorized in canon, that Tobi's intangibility works by him sending parts of his body away and then instantly bringing them back, which admittedly doesn't make ANY sense, but that's what the author gave us.