A Computerized Artificial Intelligence based program on the frequency distribution was recently published. It weights words at percentage of usage.
This work confirms the rational behind Chinese Language Proficiency Tests – e.g. the – HSK Hanyu Shuiping Kaoshi (汉语水平考试) – Tests.
For a list of updated Characters tested in the latest iterations of the HSK – click here:
http://blog.nciku.com/blog/en/2011/03/09/hsk-character-list-and-stroke-order-animations/