Interesting read and claim has been independently verified by somebody from Microsoft.
Greg Kroah-Hartman is a longtime developer of the Linux kernel, known for his work maintaining USB drivers as well as for packaging the SUSE kernel at Novell. O'Reilly Media recently interviewed Greg about his claim that the Linux kernel now supports more devices than any other operating system ever has, as well as why binary-only drivers are illegal, and how the kernel development process works.
=> How Linux Supports More Devices Than Any Other OS, Ever
This is a full-size PDF version ( poster ) from Oreilly.
Anatomy of a Linux System poster try to put most important things together. The result is indeed encyclopedic. Supporting the illustration are 19 written topics, with brief historical and educational descriptions of technologies such as Peer-to-Peer Communication, XML and HTML, Samba, Unix Command-Line Utilities, and even Java. Each topic has a list of key Web sites and useful books, including titles that don't belong to O'Reilly--part of Tim's insistence that the poster serve as a complete Linux resource. The poster also lists Linux magazines, conferences, major distributors, and, of course, major contributors.
=> Download Link [oreillynet.com] (163K)