I asked  Telstra CrowdSupport the question as “….there is no roaming agreement in place’ for Cuba, what suggestions does it have for phone & data coverage?

The reply: Get a pre-paid mobile service (including data network access) with a local mobile carrier while you’re there, so you can make outgoing calls. If you want to be reachable on your Australian mobile number while you’re there, it’s most likely possible to set up call diversion to an international number – once you know your pre-paid mobile number in Cuba. You probably won’t be able to set up the call diversion from Cuba on your own, but will need to contact Telstra. (I’m not sure if Live Chat consultants can do it for you, but you can certainly call Telstra from Cuba.)

In the end we have a Roaming Sim & might purchase a pre-paid Cuban card whilst in Cuba.

June 2nd update: We’ve been playing with our Roaming sim in our 3G iPads & it works. That is, if you have an iPad that can take a sim card, your Roaming sim (assume it’s data enabled) will work. That means, I am write this blog off-line and upload image and blog via the iPad 🙂