How Stuff Works: Operating Systems 
Unbiased enlightening tutorial with impartial description of how OSs work, and many related links.
http://www.howstuffworks.com/operating-system.htmOperating System Sucks-Rules-O-Meter
The web-based operating system quality and approval metric.
http://srom.zgp.org/
Internet Operating System Counter
Statistics on Internet OS use, WWW, FTP, and News servers. Over 940,000 hosts checked in this 1999 survey.
http://www.leb.net/hzo/ioscount/
OSNews: Exploring the Future of Computing
Weblog style online magazine on operating systems and computing environments. Daily updates, reader forum with many comments.
http://www.osnews.com/
Convergence International
The non-Wintel user group, supporting Acorn, Amiga, Apple, ARM, Be, NCs, PowerPC, Psion, Unix and other alternative operating systems. Services include a non-Wintel news summary.
http://www.convergence.org/
Operating System
Growing article, with links to many related topics. Wikipedia.
http://en.wikipedia.org/wiki/Operating_system
