Perl rules the cgi scripting world. No argument with that. But when it comes to dedicated web scripting languages embedded in the web server the case can be made for this statement to be true.
The latest PHP usage numbers from Netcraft are in. Out of 7,370,946 visible domains on the Internet, 795,034 (10.79%) showed they were on servers with the Apache module version of PHP installed. Of the 7 million+ visible domains, 4,078,326 domains are on Apache or Apache-derived servers capable of running the Apache module version of PHP and PHP is on 19.49% of those.
To answer our question we need to look at the two main contenders: ASP and Cold Fusion. Consider that there are 1,632,440 IIS-driven domains. Let's be generous and say that perhaps 75% of the IIS-driven domains use some sort of server-side scripting. That leaves 1,224,330 domains. And if ASP has 60% of that market, that gives it 734,598 domains with 489,732 domains to be split up between Cold Fusion and others. If we look at domains running Netscape servers, we see 557,498 of those. Assuming the server-side scripting is split up between Cold Fusion and LiveWire and others, this might give Cold Fusion another 200,000 potential domains if we are being generous, again.
The marketshare percentages used here were completely pulled out of a hat (a red one, actually) and have no factual basis. They might be completely different. If either ASP or Cold Fusion is on more domains than the Apache module version of PHP, then the other is way behind. But, if our rough estimates here are correct, PHP could very well be ahead of both ASP and Cold Fusion. We don't know about you, but we think that is pretty cool.