Here are couple of things that may help some others. CDMA phones will work in China/Hong Kong, but like you said it will be expensive. I work for VZW and our CDMA phones work in over 40 countries around the world. We also have “global” phones that work in over 200 countries and it is possible to have the GSM portion of the global phones unlocked after you have them for 90 days. However, one of the best values with VZW is a Global Blackberry like the Storm or Tour (coming out on 7/12/09). $64.99 /month gets you unlimited email and web on the device with a voice plan!

There is also a Prepaid Global Carrier Recommended by Consumer Guru Clark Howard: MaxRoam (http://www.maxroam.com/)
They offer very discounted rates using their SIM and an unlocked phone!

One other piece of advice to consumers – when looking for devices (GSM or CDMA/Global). The best device would be a dual platform (GSM & CDMA), Quad-Band Phone. This would give them the best coverage in any country.. CDMA in the USA and some other countries and GSM for those countries that don’t have CDMA networks. This would also give them access to all major frequencies used: 800 / 1900 Mhz CDMA and 850/900/1800/1900 Mhz GSM with the addition of 2100Mhz HSPA/HSDPA 3G Service (for countries like Japan).

With the evolution to the 4G LTE Networks, this will hopefully become a much easier process in the next few years!