Editing a Word document through Internet Explorer. Click to enlarge. Source: Microsoft

LOS ANGELES -- Windows 7 isn't the only product making its debut in this red carpet town. Microsoft is announcing Office Web applications, lightweight versions of its main Office applications that will run in any Web browser.

The news comes during day two of its Professional Developer's Conference, the two-year developer confab for all kinds of Microsoft platforms and products.

It also is a truly untethered release of its ubiquitous Office applications for the Web, following its Office Live launch, which was mainly about sharing documents rather than creating them on the Web. With today's news, Microsoft is signaling an even bigger focus on offering its tools in Web-based applications as rivals increasingly offer similar productivity tools over the Web.

Office Web will consist of Microsoft Word, Excel, PowerPoint and OneNote, a note-taking utility available for Office users. It will run in Internet Explorer, Firefox, and Apple's Safari browsers.

Microsoft (NASDAQ: MSFT) is not giving a release date for Office Web, but said it plans to update the suite more frequently than it would with its traditional Office applications, which usually come every three to five years.

"You may see a more aggressive set of ongoing releases for the Web components thereafter, so you shouldn't expect it will be three to five years before you get new components of the Web apps," Janice Kapner, senior director for IW communications in the Information Worker group, told InternetNews.com.

Kapner said this is not meant as a response to OpenOffice, the free Office suite, which is a competitor to Microsoft Office.

"Ray's [Ozzie, chief software architect for Microsoft] strategy for software plus services has been in the works for some time. Where Office fits in has been in the works for quite some time," she said. "For us, it's a response to changing climate, changing customer expectations and delivering the choice and flexibility people need."

Ozzie kicked off the PDC conference Monday with the unveiling of Azure, a new cloud-centric operating system and services for building massively scalable, Web-based software services. On top of Azure are five services, including SharePoint and SQL services, but Kapner could not say if Office Web will consume those services or not.

What that means is there are some scenarios where people will want the full, rich functionality and offline capabilities of Office installed on their computer so they can work on an 85-slide presentation during a plane flight, and then there are also some scenarios where people might just want to do a quick edit from a Starbucks or on their mobile phone.

Because it's still very early in the product's development cycle, Microsoft won't discuss pricing or full feature details, but it did say that the ribbon UI in Office 2007 will be available in the Office Web applications.