Microsoft on Wednesday announced that its Windows Phone 7 OS has been released to manufacturing (RTM) and delivered to its partners for inclusion on new smartphones that will be provided to consumers in the months ahead. The company declined to announce a launch date for the platform, but Windows Phone 7 is widely expected to ship in October or November.

"We're very excited to say that we've reached the biggest milestone for our internal team, the release to manufacturing (RTM) of Windows Phone 7!" Microsoft's Terry Myerson wrote in a blog post. "While the final integration of Windows Phone 7 with our partners' hardware, software, and networks is underway, the work of our internal engineering team is largely complete."

Microsoft also announced some very minor, feedback-related changes that it made to Windows Phone since an earlier Technical Preview build. These changes all related to Facebook integration on the platform, including such things as adding the ability to "like" Facebook posts and post to friends' Facebook walls from within the phone's integrated experiences.

Windows Phone 7 is an all-new smartphone platform that will, over time, replace Microsoft's creaky and ancient Windows Mobile system. Though based on similar underpinnings, the two platforms are completely different and incompatible, and Windows Phone features several innovative interfaces that aren't found on Windows Phone or today's leading smartphone systems, such as the iPhone and Android. Key among these are the integrated panoramic experiences, called hubs; the Metro user interface; and a deep integration with online services that largely obsoletes the in-out-in-out application experience popularized by the iPhone.

Microsoft also noted that Windows Phone 7 is the most thoroughly tested mobile platform it has ever created. "We had nearly ten thousand devices running automated tests daily, over a half million hours of active self-hosting use, over three and a half million hours of stress test passes, and eight and a half million hours of fully automated test passes," Myerson wrote. "We've had thousands of independent software vendors and early adopters testing our software and giving us great feedback. We are ready."