"The largest US corporations are bucking the trend toward open source Web server deployments, according to an ENT study of Fortune 500 Web sites...."
"But an ENT study using an Internet tool on the Netcraft Web site (www.netcraft.com) against the corporate identity or brochure Web sites of Fortune 500 companies returned very different results. Microsofts Internet Information Server (IIS) is the most common Web server in the Fortune 500, powering 208 sites or 41 percent of the list. The iPlanet/Netscape-Enterprise Web server dominates the biggest of the big. The Web server runs seven of the 10 largest corporations Web sites, and owns nearly 60 percent of the top 100 of the Fortune ranking. Overall, Netscape-Enterprise held 35 percent of the 500 deployments. Sites running Apache accounted for 15 percent of all Fortune 500 Web server deployments. The open source Web server garnered an increasing share of the Web server pie as the overall size of companies becomes smaller...."
"The dominant position of Microsofts proprietary IIS in the Fortune 500 makes Windows NT a lock for the most used operating system undergirding the Web servers -- 43 percent...."