Canadians & Americans will value the advice contained in this June 7 Globe and Mail article and the NY Times August 1 article on optimal strategies to stay in touch at a reasonable cost when traveling outside North America.
June 2009
http://www.theglobeandmail.com/news/technology/personal-tech/avoid-the-shock-of-cellphone-roaming-charges/article1594208/
The New York Time follows on August 1, 2010 with its take on it:
http://community.nytimes.com/comments/travel.nytimes.com/2010/08/01/travel/01prac.html
Talk, download, and send messages at a reasonable cost. Stay in the know without expensive roaming charges. Know what to do.