Interesting. Links from quality Chinese websites as well as other foreign language sites will help SERP in my opinion.
When optimizing US website, I'd buy US links only. But you can make an experiment and place PR8 link and write your experience in a month or so?
There is no partiality in backlinks unless it is from a legal site. If its a high traffic site, then you're lucky. Don't bother about .cn domains.
The question is how Google can understand relevancy of the Chine site;-) I think such link is not so helpful if you use English anchor text.
It is hard to define whether they are good or bad. It is also depend on your prior backlinks profile. If your website had already acquired links from trusted website then it would not bad in having links from any website even in .cn. However, in common terms - the backlinks from websites based in China could only help your ranking Google.cn (Google.com.hk currently) over Google.com. It is regardless whether the language that Chinese websites are using. (English / Cantonese / Mandarin)
site quality, high PR is the key point. This thread inspired me to add translate-tool-plugin on my site, so that foreign visitors can understand it.
If you are targeting on ranking in Google.com.hk then this link building strategy might a good idea. You should aware this kind of links may not help you ranking in Google.com as you may expected.
It's not like any backlink would hurt your site but it could bring more traffic. I just got a deal from a guy in China.
It really doesn't matter what is the extension/language of a site, where you're getting a ink from. The thing which matters is the PR and authority of that site...
u can getlinks from .cn sites but theme is much important. Try to get links from same theme and genuine sites