Just over a week after Microsoft handed Windows 7 Release Candidate (RC) to the public, the new operating system's market share gains have started to slow, according to data from Web metrics vendor Net Applications.
As of Thursday, Windows 7's overall share of the operating system user base was 0.39%, an increase of 18% over the same day the week before.
Microsoft delivered Windows 7 RC to the general public late on May 4, saying it would not limit the number of downloads and would make it available until at least the end of July.
Since its release, Windows 7 RC's market share crept up from 0.27% to finish the May 4 workweek at 0.36%, then jumped to 0.47% last Saturday and up again to 0.5% Sunday before slipping back to 0.39% Monday.
Its week-over-week gains, however, show that Windows 7 RC's pace has slowed after an initial surge. Monday's week-over-week increase of 44.4%, for example, was followed by Tuesday's 40.7%, Wednesday's 25.8% and yesterday's 18.1%.
Microsoft has declined to comment on the number of copies of Windows 7 RC that have been downloaded this week, or to characterize the pace or volume of RC downloads.
The larger share Windows 7 enjoys on weekends is no surprise, since it's much more likely that users have installed it on their home computers -- which comprise a much higher percentage of the systems in use on weekends -- than on company PCs and laptops.
Even so, last Saturday's and Sunday's week-over-week gains were relatively modest -- 20% and 20.5%, respectively -- and smaller than the increases seen May 2-3 compared to April 25-26, when users were still running the Windows 7 beta released in January.
In comparison, Windows 7's seven-day average share of 0.41% was less than half that of Linux during April (1%) or the ancient Windows 2000 (1.2%), and just a fraction of the 62.2% owned by Windows XP, which Windows 7 hopes to replace.
Net Applications measures usage share by identifying the operating systems running on computers used to surf to the 40,000 sites it monitors for customers.
The company has published Windows 7 daily share data on its Web site.