A commenter on my previous blog entry, Yong Huang, pointed me to some wonderful research he did using search engine results to compile a list of Chinese characters in frequency order. I managed to miss his comment when he posted it back in March (d'oh. I really should have paid more attention to my blogger settings), but it's an interesting read and technique:

http://yong321.freeshell.org/misc/ChineseCharFrequency.html