Which makes sense - Microsoft wants to sell applications and services - regardless of the device you own. Apple wants to sell devices, regardless of the application you use.
Ironically, Microsoft/Apple have developed into potentially very strong partners. If Microsoft starts to move away from being a hardware company, they will be a great fit.
Why? Apple is the leader; why should they bow down to the level of inferior competitors? Microsoft didn't refer to iphones and ipads out of the goodness of their hearts; but because these devices are the devices of choice for the creative crowd.
Uhm for example because office/onenote on android/iphone works great and are completely cross-platform (with Linux you are confined to the browser but oh well)?
Ironically, Microsoft/Apple have developed into potentially very strong partners. If Microsoft starts to move away from being a hardware company, they will be a great fit.