I'd have to disagree with a few of the points:
2.) I don't think that having several versions makes things murky, since people usually just do what the computer guy at the store tells them.
5.) The biggest failure of the Xbox 360 wasn't even understocking. It was not having more publishers on board with launch titles, and not getting the publishers with launch titles enough support. Dead or Alive 4 was supposed to be a launch title; I got my 360 on December 24th (a month late) and it was still a couple weeks before DoA was ready. Gears of War was also supposed to be a launch title based on Unreal Engine 3; it is not due until November -- a full year late.
7.) That .NET and Open-source initiative are incompatible is folly.