It used to be simple. US letter size paper and A4 formats; "-or" and "-our" suffix reconciliation, etc.
But now what is a marketer to do. The goal of social media and rising marketing tools is to create viral momentum - across broad networks. Certainly nodes of those networks will have common demographics, and to a large extent geography. But as globalization increases the homogeneity of networks decreases - and that decrease elevates the messaging challenge for marketers.
Certainly a critical challenge for B2C marketers, this is also a challenge for B2B marketers albeit of slightly smaller magnitude. (For some fascinating background on cutting edge B2C trends - shown through examples rather than dry commentary - check out Trendwatching "Innovation Extravaganza", Trendwatching "F-Factor - Friends, Fans & Followers", and sign up for regular updates from Trendwatching and Springwise.)
The good news is that increased globalization slightly blunts sensitivities to local idiosyncrasies. So your marketing targets will be less sensitive than in the past. Nevertheless cultural norms are deeply embedded and must be respected.
There is no clear answer. Risks abound. Good judgement built upon broad global experience is key.
Marketers must test, sample and closely monitor - and quickly change / update to accommodate the market feedback they receive.