As we mentioned earlier we’ve been working for the past few months on turning the Content Security Policy specification into working Firefox code. (You’ll remember that CSP is a framework to protect websites from XSS and related attacks). We are happy to report that the work is nearly finished, and we have some preview builds available for you to try out.

I've mentioned the CSP before. I said then it could be huge. I stand by that statement. This is *the* most exciting thing I see today in browser security.

A Glimpse Into the Future of Browser Security at Mozilla Security Blog