This is Robert . I am a Chinese Canadian living in Montreal Quebec. I think I can answer some of your questions here ,
The answer is based on the situation of Mainland China, excluding Taiwan or Hongkong.
* I would like to know how popular BitCoin is in China? Are there already some "real life" shops where you can pay by BitCoin?
There is a tiny tiny number of people who is aware of this ,there is no news about Bitcoin circulated on the major media controlled by the government ,as you know, 99.99% of Chinese populaton don't read English and there is Great Fire Wall preventing people getting in touch with the outside world .Let alone the real life shops.
As far as I know ,there are around 150 users on this forum who speak Chinese (data from the leaked MtGox email addresses).So ,it is safe to say it is very unpopular.
Once there are more news coming out in Chinese Media ,I don't know what will happen.
Instead, I've seen reports from major website like Tencent, Sina. There are quite a lot of people who know bitcoin, but most of them do not think Bitcoin will success, and have no interest to get in. Chinese are realist.. GFW is used to block informations that government do not want people to know, while Bitcoin is not strong enough to be noticed.
150 is not the real number. Do you think those Chinese science geek will use QQ or 163 as their daily email? Most of them will prefer gmail.
* Are there any laws against secondary currencies like BitCoin or some official statements from the government?
There is now laws against now, however you won't be benefiting from it unless you have certain connections.
Under the existing economy structure , banks are strictly controlled , Bitcoin will soon be banned or manipulated by a government-controlled bank once it became popular in Mainland China.
haha. You are too confidence on GFW. If it have ability to kill bitcoin, it can also kill BT and Emule. But BT and emule are living very well in China till now.
*Are there already some manufacturers out there who are accepting BitCoins?
Not at all! Although there are some traders sell on Taobao.com (Chinese version of Ebay , controlled partially by Yahoo!)
Are there already some manufacturers in other country who are accepting BitCoins?
As I know, Sharkroman, a major Bitcoin seller in Taobao, who sell nearly 3000 Bitcoins in June.
Hope this be of some help to you