:) & <

here is an link to a website where you can test any url to see if it is blocked or not in China.
http://www.greatfirewallofchina.org
I'm not sure how accurate it is... I tested my webstie, that is absolutelly apolitic and doesn't have any disturbing content, but it gave me that I'm blocked in China. Maybe that's the reason, why I never get any visitors from China... I don't know why they would block it...