Microsoft isn't usually guilty of overhype, but if you go to the Microsoft HoloLens Website you can watch this promotion video:
Then there's this demo promoting HoloLens playing MineCraft:
Why is it overhype? In truth Microsoft reins in expectations a bit. Tech Times says, "The company plans to release it at some point in 2016, but the focus will rest on developers, still, and the enterprise."
Okay, so consumers shouldn't hold their breaths. But why is it overhype? Well, in truth I have no hard evidence, but I believe the HoloLens will require a great deal of setup prior to use in any new setting. I don't think the software has any idea where your walls and tables are. Animations have been added to the promotion video, and the demos are very carefully prepared and staged. In the promotion video flat screens displaying soccer matches, video games and Netflix appear on walls, but I'm sure the required setup is detailed and involved. In the demo video I believe the locations of the wall and table have been very carefully preset and programmed in. Just look at all the paraphernalia attached to the camera they use to provide a perspective for the viewing audience.
These problems and many others I can't even think of *will* be solved, and then it will be amazing, but I believe it will take a while.
The Developer edition will be released in early 2016. At $3000. Which suggests that it might take some time to get it down to consumer prices. Meanwhile Oculus and Sony are moving ahead with their own projects. HoloLens may be technically superior but if it takes too long to release a consumer version, it may be too late for that market.