Microsoft today said it will host a launch event for the Windows 8 beta on Feb. 29 in Barcelona, the site of the Mobile World Congress.

Previously, Microsoft had promised that it would distribute a public beta -- the company used the label "Consumer Preview" instead -- in "late February." Wednesday, Feb. 29, is the last day of the month.

Microsoft did not offer any additional details on the Consumer Preview, including whether it planned to also introduce it at a similar U.S. event. A spokeswoman said that Microsoft would provide more information at a later date.

The company will not present the Windows 8 preview at the Mobile World Congress (MWC), but instead at a Barcelona hotel between 3 p.m. and 5 p.m. local time. The MWC runs from Feb. 27 through March 1.

Microsoft will open the Windows Store to the public at the same time it ships Windows 8 Consumer Preview.

Although the company today again declined to comment on a ship date for the final edition of Windows 8, the Consumer Preview's timing hints at a fall 2012 debut assuming the company paces Windows 8's development and testing as it did Windows 7's.

Windows 7's first developer-oriented release was at the end of October 2008. Microsoft offered a public beta of the OS in January 2009, and the final version hit shelves the third week of October, 2009.

Although Windows 8's Consumer Preview will appear about seven weeks later -- at the end of February compared to Window 7's early January -- its Developer Preview launched a month earlier, in mid-September rather than Windows 7's October, perhaps making the two schedules a wash.

Microsoft would certainly prefer not to duplicate the release timetable of Windows Vista, which missed 2006's holiday selling season, not shipping until January 2007.

The company has revealed some details of Windows 8 and offered a Developer's Preview since September 2011, while other tidbits have leaked from recent builds, including the apparent death of the Start button, an iconic element that's been part of the operating system for nearly 17 years.

Windows 8 will feature a dramatic overhaul of the OS's user interface by introducing a tile-based component suggestive of Windows Phone, specially-design apps for that interface and a digital distribution site -- the Windows Store -- that will be the only outlet for those Metro-style apps.

How Microsoft will distribute Windows 8 Consumer Preview is unclear, but it probably won't reprise Windows 7 beta's launch, which was plagued with problems, including an early overload of its servers that forced it to halt downloads, an on-then-off limit on the number of copies it would supply, and a hard stop to availability just a month after its introduction.

Since Windows 7, Microsoft has been more inclusive in distributing early editions of Windows: The Windows 8 Developer Preview was opened to all -- as opposed to Windows 7's similar offering, which was not -- and that early edition remains available months after its launch.

If Microsoft sticks to previous practice, the Windows 8 Consumer Preview will not expire until this summer, perhaps as late as August or even September.

Microsoft is calling the beta of Windows 8 a "Consumer Preview." (Image: Microsoft)

Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, or subscribe to Gregg's RSS feed . His e-mail address is gkeizer@ix.netcom.com.