Once again, Apple did not cave to the “bigger players” and gave Microsoft no special treatment. It enforced the same terms on Microsoft as everyone else; if your user pays you money through an App Store app, you must use In-App Purchase and give Apple 30%.
Microsoft’s original submissions were rejected because Microsoft tried to circumvent this policy. As is now the norm, Microsoft got around the ‘problem’ the same way everyone else has. They do not allow the user to upgrade their SkyDrive storage in the app, only via the web.
In fact, I don’t really understand why this is news at all. This is just standard Apple policy.