MLB.com has a report on the four Asian squads in the WBC.
To summarize it:
Taiwan (aka Chinese Taipei) has put Chien-Ming Wang on its 30-man roster although Wang has not said if he wants to play or if the Yankees will let him play. And there is this bombshell: The Chinese Professional Baseball League -- Taiwan's league, which is independent from mainland China.
Just in case you weren't paying attention to world history for the past 60 or so years.
Some Japanese players are jealous that Shunsuke Watanabe is getting more attention than other pitchers on the Japanese team.
China (which is not Taiwan, did you know that? Good thing I have MLB.com to keep me informed.) is having injury problems, which isn't going to help a team that will likely go 0-3 in the tournament.