Misty it was a joke, however Contonese is used in writing but is not the mainstream written language.
Cantonese has appeared in writing since the 19th century. It is used mainly in personal correspondence, diaries, comics, poetry, advertising, popular newspapers, magazines and to some extent in literature. There are two standard ways of written Cantonese: a formal version and a colloquial version. The formal version is quite different from spoken Cantonese but very similiar to Standard Chinese and can be understood by Mandarin speakers without too much difficulty. The colloquial version is much closer to spoken Cantonese and largely unintelligible to Mandarin speakers
