Today, Sun Microsystems will announce its plans for Solaris 10, the most recent version of the company's flagship UNIX-based OS. Unlike earlier releases, however, Solaris 10 will include a major new feature that's sure to cause tremors in open-source circles. Sun will issue at least one version of Solaris 10 to customers for free under an open-source license, similar to the way the UNIX-like Linux OS is distributed. Sun hopes that by rethinking its Solaris licensing strategy, the company can rekindle sales in related products and services and gain back some market share it lost to Linux in recent years.

Sun is expected to provide a free, no-support version of Solaris to individuals, schools, and corporations. Customers who want to pay for support will likely incur costs of $120 to $360 a year, Sun Executive Vice President of Software John P. Loiacono said. Or customers can purchase a version of Solaris that includes the Sun Java Desktop System, which includes the StarOffice 7 Office Suite, for $100. "From a pricing perspective, Solaris will be less expensive in any category than our Linux competitors," Loiacono told "The New York Times."

Compared with Linux, Solaris is more scalable, performs better on high-end software, and is far more mature, with software roots that date back to the beginning of UNIX. Sun says that versions of Solaris 10 will run on AMD Opteron, Intel x86, Sun SPARC, and Xeon platforms, and software written for the system will run without modification on all supported hardware platforms. In addition, the system will eventually support Linux applications via a future add-on called Project Janus. Solaris 10 will ship to customers in January, according to Sun.

Wow, now which *nix variant should I use? Solaris, Red Hat, Suse, Mandrake, Lindows…! Pretty confusing.