Whoever said they did a u-turn. This was a quote on the subject from Don Mattrick when they made the X1 reveal(kotaku)
Mattrick: "We're going to have an independent creator program... There's no way we're going to build a box that doesn't support that."
MS already stated a while ago that they were creating a program for indie developers so this is no U-turn from them or something they changed. When. At the time they were not ready to talk specifics because they have an event coming up which is build that will go into all the detail. The reason people got all bent out of shape is when the head of MS studios stated things will not change for XBLA which it will not. You have always needed a publisher for XBLA and that probably will not change. MS plan for indie developers and developers in general will change as they will open the platform to everyone.
Whatever one can say about MS, it can't be denied that they raised the bar for quality of value of download titles. From titles like Braid which created an atmosphere where indie devs can become well known names in the industry, through to titles like Shadow Complex which have blurred the line with full retail, giving us titles like Blood Dragon.
At the start of the 360, the average download game was phone-tier. Now indie devs like Jon Blow, Phil Fish and Team Meat are well known to the level that they can ironically moan about the company that gave them profile, and people actually pay attention. :D