Someone commented earlier that PHP is faster than CGI. In the real world I don't think that users notice the difference especially as so many scripts make calls to MySQL databases and that seems to slow them down anyway. I use both PHP and Perl CGI scripts and to be honest I can't tell the difference in speed for includes, validation of forms printing heredocs etc. There might be millisecond differences but who cares.And as for PHP, I don't use it much anymore at all ever since I figured out how to add mod_rewrite directives to my .htaccess to automatically pass Rev-embedded templates to a generic Rev CGI.
.htaccess is great for forcing type so you can parse files ending .html as though they ended .php or .cgi.
Cheers
Phil