That I don't know enough about to comment on, but it would help if anybody had any information on just how common this writing system is in Hong Kong, and how many people would be interested in writing on such a Wikipedia.
As far as I know, there is no newspaper written entirely in Cantonese in Hong Kong or anywhere in the world. There are some tabloids which choose to include some Cantonese characters in some of their sensational headlines, but no one, as even the proponents of a Cantonese Wikipedia acknowlege (except Mark, who insist there is, but "do'nt know about these dailys") so.
All serious newspapers in Hong Kong write in Chinese that can be universally understood by everybody who knows Chinese.
Extrememly few Hong Kongers have ever come across with materials that are entirely written in Cantonese written language, if there is ever such a thing.
No guidelines have been introduced or widely accepted by the general public on writing in Cantonese language.
All Hong Kong students(except those who choose to learn English as their first language) learn to write in the standard Chinese in schools.
formulax