Microsoft today revealed its future smartphone platform: Windows Phone 8. The announcement came as part of the Windows Phone Developer Summit currently taking place in San Francisco.

Joe Belfiore, head of the Windows Phone division at Microsoft, took to the official Windows Phone Blog to lay out all of the details. In the blog post he states that Windows 8 is a whole new chapter in the Windows Phone “story.” The new operating system, which Belfiore calls Microsoft’s most advanced mobile OS ever (one would hope), will start arriving on phones later this year. However, he also had some bad news to impart: Windows Phone 8 will not be making it to any existing Windows Phones. From the blog post:

Some of you have been wondering, “Will we also get Windows Phone 8 as an update?” The answer, unfortunately, is no.

Windows Phone 8 is a generation shift in technology, which means that it will not run on existing hardware. BUT we care deeply about our existing customers and want to keep their phones fresh, so we’re providing the new Start screen in this new update.

Leaving current Windows Phone adopters out in the cold is harsh, but it could be the clean sweep Microsoft needs to make sure all of its products are functioning within the same ecosystem. For example, the Start screen Belfiore mentioned is a Windows 8-style metro interface. It provides users with many color-palate options and eschews the Android and Apple icons for “Live Tiles,” which come in three sizes. Microsoft is very proud of those Live Tiles, and has provided a Windows Phone 8 trailer for the Start screen:

Many Windows Phone 8 features were exactly as rumored. The OS will support multi-core processing, screen resolutions up to 1280 x 768, and NFC. It will also support MicroSD card storage, a must-have for mobile media consumers. Windows Phone 8 will come with Internet Explorer 10 and Nokia mapping integrated into the platform. IE 10 is the same browser that Windows 8 PCs will use in the fall. Microsoft is also debuting a new “digital Wallet” feature that works similarly to Google Wallet, with some extra functionality (such as boarding pass storage) that recalls Apple’s upcoming Passbook app for iOS 6.

Belfiore made it seem as if Microsoft is looking to finally put RIM out of its misery when he listed the enterprise features that will be baked into Windows Phone 8. The OS will feature built-in device encryption and supports the United Extensible Firmware Interface (UEFI). The remote management capabilities of the platform will help business IT keep a tight reign on devices, and custom Windows Phone 8 “hubs” will be available for companies to provide company apps and info directly to employees.

More details about Windows Phone 8 will be rolling out in the weeks and months leading up to its release. Microsoft’s new mobile OS will debut later this year alongside the new Windows 8 PC OS. Between those new operating systems and the new Surface tablets, it looks as if this fall will be make-or-break for Microsoft’s new Metro strategy.