Well if you want your users to have the ability to log into myspace, which is all a huge percentage cares about, then CGI proxy is the way to go. Either that or give an option for CGI or PHP.
And what's the best way to promote a proxy? Im running my first proxy site www.megaproxy.es and I'm searching the way to promote it. Thanks.
Basically, just submit it to every topsite you can find. There are hundreds of those. Put a big link cloud for them in your footer or whatever.
I'm making a proxy help site. www.proxyguide.org (isnt finished yet) and taking advantage of all these new proxy webmasters!