Counting Linux users is no easy task since there is typically no requirement for users to register their installations. Yet Linux distributions do try and count users in an attempt to quantify their user base and relative footprint in the operating systems space.

Red Hat's Fedora community Linux distribution has now tallied its user base, and it's a number that on the surface would make it the largest installed base of any Linux distribution, with at least 9.5 million users and possibly as many as 10.5 million. Fedora competitor Ubuntu Linux currently claims to have 8 million users.

"The total number of users has always been an incredibly difficult number to measure," Paul Frields, Fedora's project leader, told InternetNews.com. "If you total up all the unique IP's ... on Fedora 7, 8 and 9, it adds up to about 9.5 million boxes right now."

The Fedora figures come out as the major players in Linux continue jockeying for position as the dominant vendor in the space, while also competing to make inroads against proprietary software. The news also comes as Frields and his team and ramping up to deliver their next release, Fedora 10, which is slated for Nov. 25th.

Frields noted, however, that Fedora's methodology may not tell the whole story. Since the Fedora Core 6 release, the project has counted usage based on the number of unique IP addresses that check Fedora for updates.