I talked with some college students in Beijing. They do not know Google Talk. They heard Yahoo and MSN, but have never used it. They used to use ICQ and now use OICQ, which is developed by a local company Tencent, the company provides QQ.
When I visited Qingdao, my father's hometown, my relative wants me to install QQ, so they can communicate with me. I tried to set up Yahoo email accounts for them. I showed how easy this can be done, but they still felt too complicate, so I gave up and they created a QQ account for me.
I tried QQ after I come back. I tried the Chat room function. It is almost a close network within China. I do not see people from outside on the network.
No doubt this is a very active online chat network. I practice my Pinying skills a lot.
I also found an article in BusinessWeek online about Tencent.