Google Spreadsheets will allow users to import and export spreadsheets in the .xls format used by Microsoft Excel and the more generic .csv (common separated values) format, the company said late Monday. Through a Web browser, users in remote locations will be able to view and simultaneously edit data. The software is platform-neutral, meaning it can be accessed using a number of browsers, including the open-source Firefox, Microsoft's Internet Explorer or Apple Computer Inc.'s Safari.

Google will accept sign-ups at http://labs.google.com from a limited number of beta testers starting at 9 a.m EDT/1 p.m. GMT Tuesday, a Google spokeswoman confirmed.

"This further proves the legitimate usefulness of software-as-a-service applications," said Tom Snyder, president of iNetOffice Inc. The Kirkland, Wash. startup makes a free Web-based word processor called iNetWord.

Charlene Li, an analyst with Forrester Research, said next-generation Web applications such as Google Spreadsheets and Writely, an online word processor acquired by Google in March, provide much of the functionality of Microsoft Office but are not yet credible replacements.

"Google Spreadsheets is not an effort to replace Excel. And if you tried to print out stuff you wrote in Writely, it would come out all ugly," she said. "Look at Web-based e-mail. We've had it for 10 years, but Outlook still reigns supreme.