Languages/platforms used for Web apps. Any stats?

["Benjamin Livshits" <livshits () cs stanford edu>]

Are there any good studies of what fraction of Web apps are written in
Java/J2EE vs C#/.NET vs PHP, etc.

Many vulnerabilities reported on SecurityFocus.com daily involve PHP
programs. I was wondering if that's a reflection of the fact that many Web
apps out there are written in PHP. Or is it that vulnerabilities in
proprietary apps that is written in Java or C# simply doesn't make it to
SecurityFocus.com?

Thanks.
-Ben