Thanks to over-zealous copyright lobby groups, everyone has to be quite careful these days about the use of copyright protected material, whether they have a legal right to it or not. Still, a lot of it can be made easier if the company who owns the material is up front and honest about what it is ok with. Microsoft has now clarified its position, so there's no confusion about what it's happy to allow and what's not.
Essentially, stream away. Microsoft doesn't mind anyone streaming content from any of its games and that means using the in-game music and everything. You can do it on Twitch or Youtube, either is fine.
The only thing it isn't ok with, is people using the name of the game exclusively as the title for the video or stream, as that could confuse people thinking it was an official video made by Microsoft.
"Your Items may not use the name of the Microsoft Game in their title to give the impression that Microsoft is the source of the Item, or authorized or endorsed the Item," the company said in an official update. "Items that make referential use of our titles are fine, for example, "Let’s Play Forza Motorsport 5" or "Tips and Strategies for Halo 5." Using the Game title to tag your Item on social media is fine. We also don’t object to "Red vs. Blue" or "Operation Chastity". But we may object to "Halo: Covenant Strike," for example, if it could be confused as something Microsoft produced or licensed, or if it could be mistaken as an official part of the Game. We just want to make sure consumers don’t get confused."
Major Nelson also reiterated that Microsoft isn't interested in going after streamers or content creators and it loves that people are so passionate about Xbox and other games Microsoft is involved with.
