Apache losing ground as Internet expands

[David Munson]

http://www.tgdaily.com/content/view/34342/118/

According to the article, Apache is rapidly losing share to IIS as the
Internet continues to grow at 5% per month.

Any ideas why this might be? Is IIS easier to set up? Easier to
secure? Are these legit servers, or maybe malware servers? I'm not
very familiar with webserver software, but isn't Apache FOSS, and even
included with some distributions?