Microsoft's delivery of Windows 7 Release Candidate (RC) earlier this week boosted use of the new operating system by 22 percent since Monday, according to data from web measurement company Net Applications.
Windows 7's overall usage share, however, remains tiny: one third of 1 percent as of Thursday.
Late Monday night, Microsoft posted Windows 7 RC for public download, several days after making it available to subscribers of the MSDN and TechNet services, which cater to developers and IT professionals, respectively.
The new operating system's share didn't budge Tuesday, remaining at the same 0.27 percent it had the day before. By Wednesday, Windows 7's share climbed to 0.31 percent; by Thursday, it was 0.33 percent.
By comparison, Windows 2000 powered 1.12 percent of all systems during April, according to Net Applications, while Windows Vista accounted for 23.9 percent. Windows XP, as it has for years, led all operating systems with a 62.21 percent share last month.
Microsoft declined to comment on the number of copies of Windows 7 RC that have been downloaded this week, or to characterize the download pace or volume.
The RC may be off to a slow start because of the changes Microsoft made after a server meltdown last January when the company released the public beta. Rather than limit the number of downloads -- something the company tried to do in January -- Microsoft has not set a download cap, and will make the RC available for three times longer than the beta.
Not surprisingly, Windows 7's share has jumped on weekends, when home computers comprise a much higher percentage of the systems in use. It's unlikely that many work PCs are running the preview, since unreleased operating systems are typically not officially approved for anything more than testing. Last weekend, for example, Windows 7 topped out at 0.39 percent on Saturday, then fell slightly to 0.34 percent on Sunday. Its share will undoubtedly climb this weekend as well.
Net Applications measures usage share by identifying the operating systems running on computers used to surf to the 40,000 sites Net it monitors for customers. The company posted Windows 7 daily usage share data on its website.