A listing for Halo Bootcamp appeared in the Korean Ratings Board, leading to speculation about just what it was.
Microsoft confirmed the existence of Bootcamp, but stated it had nothing to do with the Xbox One or the second Halo Trilogy: "What's Bootcamp? It is not related to our Xbox One efforts, or the Reclaimer Saga, but rather a project we're very enthusiastic about and will have more to say about in the near future."
The description reads:
Could this be the long-awaited PC port of Halo 3? Stay tuned.
Halo Bootcamp confirmed by Microsoft, not related to Xbox One
26 May 2013 | By JonahFalcon