The Netcraft survey this month said that
This month is the first time that a Windows 2000 site has appeared in the 50 top sites which have the longest period of time since last reboot. www.byteandswitch.com has been running continuously since November 2000. When we first started graphing web servers uptime in the summer of 2000, many people were skeptical that a Windows machine would ever make the top 50. Perceptions change, and although two years is exceptional, several Windows 2000 sites have run for more than a year without a reboot.
And a co-worker of mine brought up the following relevant snippet from a web forum:
> Hat schonmal jemand WINDOWS auf einer echten 24/7 Umgebung gesehen?
Aber ja! 7 Stunden Uptime an 24 Tagen im Monat;-)
> Has anyone ever seen Windows running in a real 24/7 environment?
Sure! 7 hours of uptime on each of 24 days in a month ;-)