Microsoft appears on track for autumn Windows 8

Microsoft Corp appears to be on track to release its new Windows 8 operating system in time for the crucial U.S. holiday shopping season after making a "release preview" of the new code available for download on Thursday.

Windows 8 is the latest version of the flagship product, which still provides almost half of the world's largest software company's profit. It is the first version that will run on tablet computers as well as PCs, providing Microsoft's first real challenge to Apple Inc's iPad.

"The progress Microsoft is making leads me to believe that Windows 8 will be available in time for the holiday season this year," said David Johnson, an analyst at tech research firm Forrester. "I've been using the consumer preview for several weeks, and while it's obvious more finishing work is needed, it has been stable and reliable."

Microsoft's release preview is similar to what the software company used to call a "release candidate," meaning the product is all but finished. The next stage is "release to manufacturing," when Microsoft hands the code to PC makers such as HP, Dell and Lenovo to install on new PCs, laptops and tablets.

Based on the timeline for Windows 7 three years ago, Microsoft is on track for full release by October or November, when machines running it will be available in stores. The company has never put a firm date on the release of Windows 8, but says it aims to have a new system every three years. Windows 7 debuted in October 2009.

In the meantime, in order to prevent a drop-off in PC sales, Microsoft said on Thursday that customers who buy Windows 7 PCs between now and January 31 can get an upgrade to Windows 8 Pro for $14.99.