The ‘Language’ vs ‘Dialect’ Debate: Is Cantonese its own language?

The Economist has published an article on their website this week about the outrage caused when Hong Kong’s education department claimed that Cantonese was not an official language of Hong Kong. Its speakers argue that Cantonese is a language in its own right, but the education department’s perspective is that it is merely a dialect of Chinese, like Mandarin and Shanghaiese. The article discusses the important differences between a ‘language’ and a ‘dialect’.

What is your opinion- do you see Cantonese as a dialect or an institutionalized language? And can you think of any similar examples of languages which are often labelled as dialects, and vice versa?