Of course there is. Cultural relevance is a key element of communication, and all markets are conversations. Cultural differences in English speaking countries are many and varied. Currencies, media, laws and regulations, political structure, education, religion, cuisine, art, customs, sport, humour, technology, agriculture, climate, resources and military relations are all factors in local culture.
If you restrict the list of English speaking countries to only those with English as an official or first language, you've got countries such as Australia, Canada, New Zealand, USA, UK and the Cayman Islands. Aside from English, these countries do not have that much in common, they all have their own slang and colloquialisms.
Australian cultural references such as the Skyhooks and the tall poppy syndrome will be lost on many people overseas, while cultural stereotypes like BBQ shrimp, Foster's beer and Crocodile Dundee are more well known. We're a melting pot, believe in the underdog and have a sense of humour many other cultures do not understand. Even the Aussie BBQ has a different style to the American BBQ.
Canada is bilingual, Ireland has more history than you can shake a stick at, England has a national anthem about their Queen, the USA has the right to bear arms, New Zealand has the haka and the Cayman Islands is famous as a tax haven.
Richard McManus says Remember that one of the cardinal rules of web design is that you must understand what the user wants.
That may be true, but the first rule of Business 2.0 is knowing who your customer is.
While more than one have missed the point, services like gnoos are valuable because they know who their locals are, they know what being local is, not because they hire someone to teach them how to be like a local, they actually are local.
For local consumers who see ads with people wearing the wrong clothes and speaking with the wrong accent, it's just not cricket. If you want to speak to a local market and have them listen, or build a community, you'd better learn more than the lingo mate.