Microsoft is ending production of its Kin line of mobile phones, just a few weeks after US launch and days prior to their projected European debut.

That Microsoft would kill a product this early in the production cycle is a stunning change of strategy. Stunning also, given that Microsoft opted for a very different character for these devices: essentially feature phones with rich social networking capability. This approach was strikingly opposed to its traditional it’s-all-about-Windows-OS approach of the past. And it cost the top people in Microsoft’s gaming and mobility division their jobs.

What’s really sad about the loss of Kin is that Microsoft will now return to its strategy of pushing the Windows OS (Windows Phone 7) – and doing so into a marketplace where the OS has become nearly irrelevant. It’s the application model which now controls the marketplace and Microsoft long ago became a non-player in that arena. Apple’s CocoaTouch (backed up by the iTunes App Store) and Google’s Dalvik (backed up by the Android Marketplace) both have solid cores of developers – who are able to make money in these markets without being hampered by the constraints of carrier-approval. And there’s yet another core of developers pushing the limits with HTML5 and Javascript. For a broad class of applciations, this mobile web application model works fabulously on mobile browsers based on Apple’s open sourced WebKit – including Apple’s Safari on iPhone and Google’s Android Browser, along with Nokia’s Web Runtime. Perhaps needless to say, Microsoft’s mobile browser – Pocket Internet Explorer – is not based on WebKit.

Further, Microsoft’s traditional hardware partner for mobile devices – HTC in Taiwan – has all but abandoned them in favor of Google and its hot-selling Android OS. HTC got PocketPC and Windows Mobile off the ground in the early part of the decade with HP’s striking and successful line of Personal Digital Assistants, called iPaq. Later, they built a long list of mobile devices running the Windows Mobile operating systems and branded by carriers. But, after the solid (if low-key) success of its first Android phone, the Dream device – branded by TMobile as the G1 – HTC has been going to market with its brand in the forefront. Without Microsoft.

Microsoft, once the undisputed king of the industry (not to mention the stock market), looks in total disarray in the mobile space.