Check this page for Google service availability in mainland China
The above link goes to a Google page that offers a summary of accessibility to Google services from within mainland China , as you can see , many great service has been blocked by the Gov. especially Youtube , everybody love Youtube , but you just can’t use Youtube in mainland China.
But thanks GOD we have VPN to unblock Youtube in China , personally , i recommend overplay and StongVPN to watch videos online , because these 2 provider have VPN plans optimized for stream online videos , and both have great speed and support .
If you are planning a visit to mainland China , VPN account is a must , many many great website blocked in China, such as Facebook, Youtube, twitter and any porn site ,any poker sites. grab a VPN account to unblock them all.