The UTC is considering two changes relating to properties for the Unihan
database. PRI #225 proposes transforming the data for the kHanyuPinlu
field so that it also uses accented pinyin. PRI #226 proposes
deprecation of the kCompatibilityVariant field.
For details of these see the PRI pages:
http://www.unicode.org/review/pri225/
http://www.unicode.org/review/pri226/