Thank you for the heads-up, Ted. Getting ever more anxious for this new sim to arrive when it's ready!
With regard to Windows10/Xbox, Microsoft/Asobo have said all along that their main focus was development of the sim for hardcore PC sim users, on the Windows10 platform, and that it is a true flight simulator, unlike MS Flight (in their own words). The development of the sim for Xbox is an extension off of the development for PC/Windows10, not the other way around. Asobo's own employees are using the sim all of the time, and they use it on PC's with joysticks and rudder pedals, etc., not Xbox controllers.
With regard to bandwidth requirements - in order to see the sim with all of the new, stunning real world graphics (based on satellite data, photogrammetry cities and vast AI-based autogen the world over), you'll need to have an active internet connection to connect to the Microsoft servers so as to have access to that over 2 petabytes of data (there's no other way of doing it). My understanding is that the speed of your internet connection and your frame rate determines how much and at what quality of scenery is actively displayed. You don't need an internet connection to use the sim, but the scenery will be more generic without it (like stock FSX/P3D type scenery, from what I've heard). Also, you can cash the downloaded scenery while you're flying on the internet connection, and then you can fly in that same area, with the same full-quality/detailed scenery, without being connected on the internet.