"http://www.techweb.com/showArticle.jhtml?articleID=196601406"

"Both T-Mobile and Cingular had an advantage not available for Verizon
and Sprint users: their GSM-based phones can usually be used in many
non-U.S. countries, CR observed."

That's great news, as there are certainly a lot of non-U.S. countries.

Actually, you can use CDMA phones in a lot of non-U.S. countries as
well, just not as many as with GSM phones. And there are several
countries where CDMA works but GSM doesn't, including Japan and Korea.
CDMA is growing by leaps and bounds, with a lot of new deployments in
4Q2006, and more coming next year, especially at 450MHz.