Microsoft plans on Thursday to start public testing for the first, although the technology preview is at least as notable for what it doesn't include as what it does offer.
The limited test of the so-called Office Web Apps includes versions of Word, Excel and PowerPoint, but not the OneNote note-taking application. And while Excel and PowerPoint offer the ability to edit and create documents, the current Web-based version of Word can only be used to view documents, essentially the same capability it already offers as part of its current Office Live Workspace product.
Microsoft said the Web versions of OneNote and Word share "the same editing surface," and that the technology is still being worked on.
"We made the hard decision to turn off editing in the Word Web App at Tech Preview, in order for people to have the best experience at this early stage," Microsoft said.
Microsoft plans to offer the Web Apps preview first to users of Windows Live SkyDrive, giving them 25GB worth of storage.
The Office Web Apps are scheduled to be launched along with Office 2010--the next version of Office, with both browser-based and desktop programs due out in the first half of next year. The Office Web Apps will be made available to consumers as a free, ad-supported part of Windows Live, while businesses will be able to offer them to workers via their own SharePoint servers or through the Microsoft Online subscription service.
Microsoft said it will have editing abilities for Word and a version of OneNote by the time the Office Web Apps launch in final form. The current technology preview will be made available to tens of thousands of users, with a broader beta planned for later this fall. However, Microsoft would not commit to offering editing abilities for Word by the beta release.
Once finished, the browser-based versions will all offer editing, though not all of the capabilities of their desktop counterparts. Excel and OneNote will feature live co-authoring abilities, while all the Office Web Apps will work only while a user is connected to the Internet.
Microsoft also takes a different approach when it comes to sharing documents than do its rivals. While Google Apps lets users share a document directly, Office Web Apps enables sharing at the folder level--meaning that to share a document, a user must save it into a folder on Windows Live SkyDrive and then share that folder.
Forrester analyst Sheri McLeish said that the Office Web Apps do appear to be more complicated than rivals such as Google Docs or Zoho Office.
"Google and Zoho are very easy to get started on today, requiring just a step to register before being able to work on a document or spreadsheet," McLeish said. "Microsoft's Office Web Apps do not seem to match that level of ease to get started."
On the plus side, McLeish noted that Office offers a depth not found in its online rivals.
"Once you are in the Web Apps the experience is very much the same as the desktop suite," McLeish said. "And for enterprises, deployment choices to host the Web Apps themselves on-premise is a big differentiator from Google and Zoho."
As for the current release, Microsoft noted that it is still in pre-beta form and has a number of known issues.
"It's still going to be rough around the edges," said Ural Cebeci, a senior product manager in Microsoft's Office unit.
The Office Web Apps are being certified to work in Internet Explorer, Firefox, and Safari, and may also work in Google's Chrome--although Microsoft isn't guaranteeing Chrome compatibility.
Microsoft had previously indicated on several occasions that the Safari compatibility meant that users would be able to edit documents on their iPhone, but Cebeci said that iPhone users will only be able to view documents--capability similar to that offered on other smartphones.