Apple appears to be testing Mac OS X 10.9, according to data appearing in analytics logs.
9To5Mac reports that it has been receiving page views from at least four computers running Mac OS X 10.9 that are located in the US Bay area and Apple's corporate network.
The screen resolution data collected leads to the conclusion that two of the four machines running the unreleased operating system are 15in Retina MacBook Pros.
The report notes that it is technically possible that the data is fake, but says that the "timing and IP addresses are in line with what we expect from beta testers of the next version of Mac OS."
Google Analytics for 9to5mac
9To5Mac isn't the only website to have spotted page impressions from computers running Mac OS 10.9. Apple Insider has also spotted some traffic from what appears to be Apple's next operating system, as well as other websites from across the globe.
Apple's newest OS, 10.8 Mountain Lion, was released in July, and its predecessor, 10.7 Lion, was released in July 2011, so it is expected that Apple will continue to update on an annual basis, with 10.9 arriving mid 2013.
Just last week, Apple sent out invitations to select members of the developer community to encourage them to start testing Mountain Lion OS X 10.8.3.
There's no word on what Apple will decide to call its next operating system yet. Will the company stick to its big cat theme? Let us know your suggestions in the comments section below or on Twitter.