Revealing the extent to which computer users may be seeking an alternative to Microsoft's pricey Office 2007 suite, IBM said Wednesday that the beta version of its free Lotus Symphony productivity software has been downloaded more than 100,000 times since the company made it available on the Internet a week ago.

IBM said the number represents a record for software downloaded from its Web site. To boot, the part of the company's site that hosts the software has been visited more than 1 million times during the same period, according to IBM. An online support forum for the software is receiving 600 posts from users daily, the company said.

IBM launched Lotus Symphony last week with any eye to denting Microsoft's dominance of the desktop office software market. The package includes a word processor called Lotus Symphony Documents, as well as Lotus Symphony Spreadsheets and Lotus Symphony Presentations. IBM is calling the suite "enterprise-grade productivity software" and points out that it's based on many of the same tools found in its Lotus Notes 8 e-mail and collaboration platform.

Because it's free, Lotus Symphony could present a significant challenge to Microsoft's new Office 2007 suite in the market for Windows-based productivity software. Some commercial software buyers have expressed concerns about Office 2007's price and compatibility with older applications. The software is based on a new format developed by Microsoft called Office Open XML. Earlier this month, the format failed to gain fast track approval from the International Organization for Standardization.

As an OpenOffice derivative, Lotus Symphony employs the Open Document Format to ensure cross-application portability of data. ODF is an approved ISO format, a fact that appeals to many enterprise software buyers -- particularly those in the government market. Earlier this month, IBM said it would donate portions of the Lotus Notes code to OpenOffice.org, which governs the OpenOffice project.

To date, OpenOffice has failed to put much of a dint in Microsoft's multi-billion dollar office software business. However, that could start to change in light of last week's announcement. IBM said it has tasked 35 programmers with creating enhancements for Symphony. Because it's an open source project, those enhancements will be made available to other vendors that offer versions of OpenOffice, including Sun Microsystems.

IBM's Symphony announcement takes a page from the company's Linux playbook. Big Blue is a significant backer of the open source operating system, though it derives no direct revenue from the software. Rather, IBM has created an ecosystem of customers and partners that buy IBM's commercial middleware products to tie together systems built on Linux. The strategy not only boosts demand for IBM middleware, it also denies to Microsoft some valuable market share. IBM now appears to be adopting a similar strategy in the desktop market.

Microsoft still has an edge in one key desktop segment, however. On Tuesday, the software maker said it would ship Office 2008 for the Mac on Jan. 15th. Lotus Symphony runs only on Windows- and Linux-based PCs.