Microsoft demonstrated that through HoloLens you could view the Windows interface as if it were a 3D landscape. This ability of HoloLens to project the display on any surface of the room could be used to project 3D models on desks or table tops in front of the users.
Microsoft has stated the device to be a stand-alone product, and is not something that you use with a PC or a gaming console. This device has its own internal processor and it costs significantly higher than a gaming console putting it in the same market as an Ultrabook or an iPad.
HoloLens will be released at some point during the life of Windows 10 as promised by Microsoft. If it succeeds in the market it will be because of all the good it can do, rather than because of it. Many speculate the augmented reality market to be worth $120 billion by the year 2020, which would be four times what the App store has earned in its entire lifespan.
Thus a new era of computing will be brought about with the advent of Windows 10 and with it the new and first-of-its-kind HoloLens, and will change the way we live our lives radically.