BTW, you do have some options. I'm going to Grand Cayman in a couple of weeks and I know that roaming costs will be off the hook. So, I purchased some Skype credit and downloaded the app. I will need to find a wifi hotspot (available in my room and other places on the island) I just need to hook up and I can call back to the states for about $.02 a minute. It's $1 a minute roaming via Verizon.
Verizon has a new plan for $64.99/month that offers Unlimited Data all across the world (Includes Australia & New Zealand). It's really affordable and I use it a lot.
Hope that helps!