It's always interesting to pit Microsoft and Apple together for comparisons, even more so, though, since they share a rivalry that spans decades. Ars has some cool analysis from a TechEd 2009 video. The more interesting part involves a mea culpa on the Windows Mobile 6.5 hack job:
The reason why we couldn't complete the interface on Windows Mobile 6.5 is because of time. We only spend what, eight months, nine months, to build 6.5 from ground up and it's actually an amazing engineering feat. But, in order to do that, we had to do some prioritization and we had to cut certain features. Eventually, we will make sure that the UI capabilities are carried out throughout the whole platform.
Now, compare that to Apple and the iPhone. It's hard to argue that Apple focused more on form than function (no copy/paste, no initial app store, etc.) but everyone loved the device anyway. I think it might have everything to do with first having a vision of what the device would do, focus efforts of bare-bones functionality, but make the user interface experience of that functionality look superb. Microsoft seems to have taken the opposite approach in a desperate attempt to stymie the iPhone's explosive growth, but I have an awful feeling that the me-too approach is not going to be as successful as it has been in years past with other Microsoft staples.
In all, it comes down to a difference in paradigm. Apple goes to great lengths for a quality user experience; Microsoft, flood the market with half-baked, copycat clones. If current trends are in indicator of the future, things don't look so hot for that approach.