COMING WEDNESDAY: Microsoft will release a preview of Windows 8.1, a free update that promises to address some of the gripes people have with the latest version of the company's flagship operating system.

COMING WEDNESDAY: Microsoft will release a preview of Windows 8.1, a free update that promises to address some of the gripes people have with the latest version of the company's flagship operating system.

SHOWCASE: Many of the new features have been shown off already. The Build conference, which starts Wednesday in San Francisco, will give Microsoft's partners and other technology developers a chance to learn more about it.

OTHER POSSIBILITY: There's speculation that Microsoft could show off a new, smaller version of its Surface tablet computers.