I agree that us Network Admins are going to need to make changes to our policy of just blocking everything.

The way that the web is being used today is far different from 2-3yrs ago. Companies are now using Facebook, MySpace and other social netwroking sites to get their name out there and using then as Marketing tools. As a security admin this can be a sacrey thing to open your network to these sites.

I'm already looking at several newer scanning technologies that will allow me to open these sites but still have some control on the content and the chance of security threats.