This may be related to the fallout from the Bo Xilai case and the response of the Chinese government. Colleagues have commented that they are also having problems. My proxy is very very slow through Firefox. Going back to IE9 without a proxy has allowed me access to the internet and my browser, but the network speed is still awful.

I use google chrome and have noticed no problems, esp after adding the faster browsing plugin.

It could be at a provincial level perhaps?