As someone who's written a lot about the GFW, I always remind people -- the Great Firewall only affects connections going into and out of China. For domestic traffic there is no firewall or filtering at the router level. There is another system for censorship of content on servers inside China -- good old fashioned licensing to be a "content provider" and local regulation. If you're operating inside the sovereign borders of the PRC, then there are other conventional means of controlling content, like telling your ISP to shut you down or serving your company legal notice.
So it's a fallacy to talk about the Great Firewall as the most important part of the censorship system. The majority of folks in China are looking at entertainment content on servers inside China, and not trying to lookup the latest human rights abuses on foreign servers. Similarly, Americans are more interested in Britney Spears and the latest viral YouTube video than they are researching historical abuses of Native Americans.
I'm writing this from a coffee shop in Beijing using their free Wifi (which is quite common). With all these sensitive words in the post, hope it makes it through. (Though I'm kind of tempting fate by hitting the Preview button repeatedly)
"The value of marriage is not that adults produce children, but that children produce adults." -- Peter De Vries