This is Microsoft realizing that Windows desktop monopoly, while mighty, doesn't necessarily translate to other markets, especially cloud services, all that well because the monopoly is based on compatibility and compatibility means leaving those holes that allow for third-parties to hijack the platform to deliver their services. Also in a world that kept needing new desktop operating systems, OS monopoly was far more valuable than app monopoly but in a world where a 10-year old operating system is hard to kill, app monopoly is more important, because OS has already been commoditized.<p>In this sense, their Office monopoly, which is not as reliant on third-party add-ins or platform openness, and is far more based on product superiority, is more important for them to preserve. Office gives them a strong chance at dominance in business cloud services. Since they are far ahead of competitors at this point, they want to win it as quickly as possible before competitors catch up. This has nothing to do with Microsoft conceding anything - it's simply that Office is far too important to be tied to Windows.