Remember, it will work just fine on WiFi. My Droid X in Taiwan worked just fine with a little prep work (like Maverick as an offline map, an offline Chinese dictionary, etc.). A throwaway phone for calls works, but also remember you'll be on a weird timezone - communicating via Google Voice is much more convenient than being woken up in the middle of the night
Since VZW did away with their International Email plan (unlimited International data for some obscenely low price) I don't care as much about World Phones. That said, my D2G work line will be hanging around for a while.