If you’re one of the handful who has taken a Windows Phone leap of faith, bad news: Your device is forever stuck with Windows Phone 7. People close to the company say Microsoft will only make Windows Phone 8 available on new phones that are released later this year, according to reports.

Microsoft has confirmed that WP7 apps will run on WP8, but nothing more. Why would Redmond do anything different? Think about it: Microsoft, with partner Nokia, is in the midst the biggest launch in the platform’s history with the Lumia 900. Any news that this phone will be obsolete when WP8 drops — which is just a few months away — will kill sales.

It’s not like reporters and bloggers haven’t tried to pin Microsoft down on the issue. Long-time Microsoft pundit Mary Jo Foley prodded the company for answers in March, and got the same story as everyone else. Microsoft is definitely hiding something: its “early adopters” are about to be marooned, and that nasty f-word is about to surface: fragmentation.

Android users know all about this. Google touts the latest features available on Android, but end users don’t see them because developers are too busy developing for operating system versions released two years ago. On the market right now are phones with Android 2.2 Froyo. That version of Android is now two years old, released in May 2010. Most never see an upgrade because it is the device manufacturer and carrier (not Google) who is responsible for shipping out new code. History shows Android partners do a crappy job in this department.

The developers now choose between using the latest and greatest features of Android and locking out a good portion of users, or developing applications that take into account the fact that a majority of Android users are stuck on outdated software. The lowest common denominator is always going to win as developers want their apps in front of as many people as possible.

The iOS platform is completely different, and this is due to Apple’s commitment to legacy support. The iPhone 3GS is a great example here. When launched in 2009, iOS 3 was included on the device. Today, that same 3GS can run the most current version of iOS 5 without a problem. A three-year old phone is still current, and developers are not hamstrung by a majority of users on old platforms because Apple pushes and enables users to upgrade.

Microsoft has chosen Android’s fragmented path against any good sense. While I understand this likely has to do with the drastic code changes under the hood, it still does not make sense why older legacy devices cannot be factored into the equation. Windows Phone developers must now contend with the fact that a sizable portion of the market will never be able to upgrade. Apps written for the lowest common denominator win again.

Redmond would have been far smarter to adjust its plans for WP8 and fold its early adopters into the mix. I’m willing to bet that some of the advantage that iOS holds over Android has to do with the fact that users receive first-party support from Apple for years. Purchasing an iPhone seems like better value as a result, and the consumer is happy they still have a (somewhat) current device.

Fragmentation is never a good strategy, and especially if you’re trying to push the envelope of mobile development or make some waves in the mobile space.

Pissing off the customers who just put their faith in your platform isn’t the best way to make an impression. So why do it?