BOFH wrote:

IIS, however, is a superior web server to practically everything else out there, including Apache. IIS is a commercial product, backed by one of the largest companies in the world. It is not, as Apache is, a "hobby" product written by a thousand developers who have virtually no internal communication beyond their primitive form of discussion board called a "mailing list." I hate to be so anti-Apache/Linux here, but it's one of the things which really bugs me about Linux evangelists; the persistant belief that OSS has a hope in hell of creating better products than a commercial entity like Microsoft.

Why does Apache have 67% market share then? Maybe it does not need commercial support, and if it did then I am sure someone provides it.
Amazon uses Apache as does PayPal and they are very successful commercial sites. Very good business case for Apache. Google runs Linux (and it's own home grown web server).
It proves that OSS can provide a better product. Why is CVS and PHP/Perl so popular as well?

What is good about Apache is the .htaccess files. They may not be user friendly but the do allow you to do things like redirection (which in IIS you need access to the server and need to create the file you are redirecting from).

Other things Apache can do (without admin rights to the server config):
  • Error Documents
  • Password Protection
  • Deny access (via IP)
  • Adding mime types
  • Directory index (i.e. default page in folder)
  • Prevent hotlinking (i.e. linking to images from other sites)
  • Prevent directory listing
From http://www.javascriptkit.com/howto/htaccess.shtml
Apache's .htaccess file gives a lot more power to the web developer (which can be dangerous as well as extrememly beneficial if you use it properly)

There are lots of modules available for Apache to extend it.

IIS can do things like that, but only with web.config files (and even then only if the file types are .NET - ie ASPX)