The guys at Webmasterpro have published a study that analyzes the install base of various office packages among German users. While Microsoft Office comes out top (72%), open source rival OpenOffice is already installed on 21.5% of all PCs and growing.
The method used in the study is quite clever as it neither depends on sales figures (quite difficult to assess for a free software product) nor on questionnaires (prone to sampling bias). Instead, they have equipped their web statistics service with the ability to detect the fonts installed on the computers visiting the monitored sites. Now, each office suite brings along a set of unique fonts (e.g., OpenSymbol comes with OpenOffice), which can be used to identify the installed office suites. While there are some caveats especially regarding Microsoft Office, the method seems much more sensible than previous ones. The only real problem is that they cannot measure the share of web-based Google Docs users.
When looking at the numbers for Microsoft Office one has to keep in mind that many of newly sold PCs ship with a OEM version of Microsoft Office that typically expires after 60 days. Of course, users with expired versions are counted the same way as those with regularly licensed versions. Furthermore, some other software like Microsoft's gratis viewers programs install the same fonts, therefore the authors give a higher statistical uncertainty for Microsoft Office compared to the other suites.
For OpenOffice, the number of 21.5% is already impressive. But even more telling is the trend showing that during the last year OpenOffice steadily gained 3 percentage points. But what surprised me the most is that the authors hardly found a difference between home and business users. These observations mean nothing but OpenOffice is rapidly making inroads into Microsoft's #1 cash cow!
Update: The authors of the study have now published a followup with international data.
Copyright 2006--2011 Hendrik Weimer. This document is available under the terms of the GNU Free Documentation License. See the licensing terms for further details.