PS3, XBOX Games & Consols

Hi there,
Seems to be the best place to ask advice on this subject - we are migrating to Perth in 2010 and my boys have a PS3 and an XBox.
I have read on some threads that these do work with games they bring with them but will any new games they buy there work on them? Also my son wants a DSi for Christmas - will he be able to charge it in Oz?
Advice appreciated thanks.