I guess I have written about this before, but let me sum it up a bit again.
.cn domains are definitely worth something, but mostly to the Chinese or people who have considerable interest (I mean "stake") in China. A LOT of foreigner speculators lost some good deal of money during the "rush" when the second level .cn opened up back in Spring 2003.
One of the most obvious mistake by these "losers" was that they had registered those so-called "keyword" domains which their target clients cannot even spell correctly. For instance, information or restaurants are "difficult" words even among the on-line population there who are more used to numbers or Pinyin and browsing mostly Chinese websites.
And for those who don't read or speak their language, selling (to the Chinese) itself could be hell. In short, you need to know the place (culture) in order to tap into that wealth. For others, I would suggest staying away.