Just as the landscape for mobile processors has heated up over the past few years, so too has the landscape for mobile OS's. Two years ago, the main players were iOS, Symbian and Windows Mobile. Today, Android is hot on Apple's tail and Nokia's Symbian is in its final death throes. Microsoft's revamped OS strategy will mark them as the latest contender in the mobile space as Windows 8 will leap off of the x86 train and join the fray in the ARM space. You could call this Microsoft's delaration of an ARMs race.
Microsoft and Intel (and to a lesser extent, AMD) missed the boat on the market shift to truly personal, portable computing devices. The assault was kicked off less than 4 years ago in 2007 by Apple's iOS on the iPhone line of products. The easy to use, consumer-friendly iOS along with Apple's iTunes Store have helped Apple to build up a lot of momentum by the time the first iPad was launched roughly 16 months ago. The success of the iPad has fueled tremendous growth in the tablet space, growth that Microsoft cannot ignore.
So how did Microsoft miss such a strategic shift in the marketplace? The main issue is the licensing costs for Microsoft's OS. Apple doesn't pay any licensing costs since iOS is developed in-house. Google's Android is given away basically for free to its platform partners because Google is using Android to promote and monetize it's Internet properties. Despite both Apple and Google having a large share of the OS market in mobile devices, neither company relies on selling the OS as its main profit motive. The low cost of entry for Google's Android for hardware vendors is in main responsible for making it the main OS competing against Apple's iOS.
This leaves only Microsoft as odd man out since it is in the business of selling its OS for a profit. Microsoft now finds itself in the unenviable position of convincing its hardware partners of their value proposition. Next, both Apple and even Google are miles ahead of Microsoft in terms of an integrated marketplace that encourages developers to create content for those platforms. Microsoft's linking of Windows Phone 7 to the Xbox Live service is a step in the right direction, but there is still no standard marketplace for tablet-centric app, which is the platform's Achilles heel. Despite Microsoft's sizeable warchest, their entry into the mobile space - even in earnest - doesn't guarantee a win. And they will need to create an integrated marketplace for content providers in order to have any hope of catching up to iOS and Android.