Microsoft has yet to say much about the next version of Office, but the company is starting to let a few details fly, and more information about the release schedule and features should be available soon.

While Microsoft is still keeping a lid on the full scope of Office 14, Chris Capossela, senior VP of the company's information worker group, laid out the suite in broad strokes in an interview Monday. The executive noted that with this release, Microsoft would be lending particular focus to collaboration, new developer scenarios, and evolving Office's role in Microsoft's "software plus services" strategy via new Web applications and improved mobile access.

Microsoft has begun testing Office 14 with select customers, and Capossela is already running a test version of Office 14 on his work computer. "The vast majority of the team is working hard on Office 14," he said.

However, it's still unclear when Microsoft will release Office 14. Microsoft CEO Steve Ballmer said last week that it wouldn't be released until 2010, meaning that it will likely come after the release of Windows 7.

Office Web Applications, lightweight browser-based versions of the full client versions of Word, Excel, PowerPoint, and OneNote that will include the ability to edit, view, and collaborate on documents, will be a key new element of Office 14. Microsoft demonstrated Office Web Applications at its Professional Developers Conference last October but left out many of the details.

According to Capossela, one important feature of Office Web Applications will be that files created in Office or Office Web Applications will maintain full fidelity as they are passed back and forth between the Web and client versions of Office. "Unlike Google and Zoho, we won't crush stuff the Word user created in the first place," Capossela said.

Office Web Applications will also support REST APIs, meaning that developers will be able to pull data created, for example, in Excel's Web app version, into their own Web applications. "We have a big focus on developers," Capossela said, pointing beyond Office Web Applications to the whole Office 14 suite. "Part of that focus is around new APIs, part of that is around interoperability documentation, so people can make their solutions work with Office more easily than they did in the past."

Silverlight, Microsoft's rich Web application plug-in, will play a significant role to help power the Office Web Applications' user interfaces, but only if the customer has downloaded the Silverlight browser plug-in. Otherwise, customers will be able to use a non-Silverlight version of Office Web Applications.