dunnersdude: Keen to know some more details about how this works/usage cases
I think these are the main uses cases:
Going overseas on holiday. Put money into transferwise. Buy things overseas using the transferwise card. Profit.
Buying things off Amazon\ebay. Put money into transferwise. Add transferwise card to Amazon billing and Paypal. Buy thins in USD. Profit.
Receiving money from overseas. Have overseas person put money into overseas transferwise account. Either withdraw money or leave it there and use it for your USD purchases. Profit.