Mandarian or Cantonese?

I think I am very qualified to answer this question because I am a Chinese. Actually in Guangzhou the Cantonese is the local dialect. However, I still think Mandarin is much more useful. When you go out of Guangdong Province, other people may not understand Cantonese because it's only a dialect. If you Mandarin, you can go all over China because people know it. So Mandarin is the official language in China. So when you see the Olympics, the language will be Mandarin unless you are watching the Cantonese channels. I love China

Non of Mandarin nor Cantonese is spoken in my city. We speak Hokkien. I believe that Olympics should speak in Mandarin, as Mandarin already official language in China, and Cantonese already listed as one of the dialect.

it must be Mandarin,Cantonese is just a local language in Guangdong province and Hongkong,it's not popular in most of China.but many overseas chinese from Guangdong province and tremendous influence of HongKong,foreigners thought Cantonese is authentic chinese.authentic chinese is Mandarin,so u will listen Mandarin report about Olympic games from chinese medias

i agree to, i think mandarin will be spoken most likely too. as said earlier, cantonese is a local dialect and not all chinese people understand it. you could say mandarin is the main or something. where i'm located, almost everyone speaks mandarin. there are some who do speak cantonese, hokkien and so on. but on tvs and all, it's usually mandarin.