As far as secrets go, Windows 8 -- Microsoft Corp.'s (MSFT) successor to its best-selling Windows 7 personal computer OS -- hasn't exactly been the best kept.  But thus far there’s been little official confirmation of when the next OS would drop, what platforms it would be on, and what the official name would be.

Today at the 2011 Japanese Microsoft Developers Conference Chief Executive Officer Steve Ballmer answered some of those questions.

He referred to the new OS several times by the name "Windows 8", indicating this was the likely launch title.  He also said that the release date would be sometime "next year".

As for the launch platform, he remarked, "As we progress through the year, you ought to expect to hear a lot about Windows 8. Windows 8 slates, tablets, PCs, a variety of different form factors."

Mr. Ballmer suggests that the line between tablets and PCs is blurring.  He states, "The form factor of the devices that we all use will continue to change. I think there will be a day in the future where it will be hard to distinguish a phone from a slate, from a PC. You literally will have displays that become paper thin and very easy to fold out form your phone. And at the same time, you're going to get more and more PC-like capabilities in smaller form factor devices."

While the chief executive is quite excited about this development, Microsoft may have cause for concern.  So far it's utterly failed (thanks in part to partner Intel Corp.'s (INTC) lackadaisical performance) to capture tablet market share.  

Whether a PC-geared OS suitable for desktops and laptops can be competitive on tablets versus a dedicated touch-driven operating system like Android or iOS remains to be seen.  That may be kind of like expecting your minivan to do blistering laps on the local racetrack right after dropping off the kids.

Whether it's the growing tablet pressure, addition of ARM CPU support, the inclusion of the ribbon across more of the GUI, or the quicker development schedule, Mr. Ballmer has taken to referring to Windows 8 as his company's "riskiest product".

Leaked Windows 8 builds indicate that the company is nearing the closed beta build of the operating system.  A open public beta, similar to the incredibly popular Windows 7 public beta test program will likely follow, potentially around the January timeframe.

Mr. Ballmer's remarks were largely overshadowed by the preview of Windows Phone 7.1 "Mango", early today.  The upcoming smartphone operating system will launch this fall, packing over 500 new features.