Microsoft is only previewing the SDK because there are features the company doesn't want to publicly reveal just yet.
The Windows Phone Developer Blog reports that Microsoft is now taking requests for access to the Windows Phone 8 SDK Preview program.
The object of this program, according to Microsoft's Todd Brix, is to let developers of the platform's most-downloaded apps (aka the "popular" crowd) to start optimizing their games and whatnot for Windows Phone 8. The majority of published developers should qualify for access, he added.
So why not just publicly release the full SDK now rather than offer a little pre-launch tease? Because there are a number of features Microsoft just doesn't want the public to know about just yet. "Our SDK includes comprehensive emulators that allow developers to test apps against a wide range of Windows Phone features. We recognize that this is a different approach to delivering tools than we’ve taken in the past," he said.
Naturally Microsoft's goal is to generate as much Windows Phone 8 excitement as possible to attract new customers when phones go on sale. "This [preview release] is one of many steps we’re taking to help give you what you (and we) want most," he adds. "Windows Phone 8 remains on track to hit store shelves later this year and we very much want developers to create new apps for the platform, so please bear with us."
Additional SDK news will be made in the coming weeks, he said.
To apply for the Windows Phone 8 SDK Preview program, developers are required to visit the Microsoft Connect site and complete a short application. Developers should have their Developer ID and Application’s Product ID on hand, as well as the name of their local Phone Champ (if you don’t know your local Phone Champ, you can always get in touch via the Find My Champ app).
"We’ll be taking applications until Monday, September 17 at 5pm PDT. If you’re accepted to the program, you’ll hear from us in the following week with instructions on how to download the SDK and get support for questions and issues," he said.
To apply for the program, head over to the Microsoft Connect site here.