Thankyou, very helpful.
Observations as a customer:
There is a cafe in Longreach that uses an ipad as the keypad for the cash register. As a customer there seemed to be a few more buttons to be pressed to complete the sale than say a cash register, but overall it was fairly smoothe. I did ask some questions like 'Aren't you worried someone will steal the ipad and sit in the corner making the cash tray go in and out all day?' but apparently there are some good checks and balances there to stop this, or worse it being stolen.
There's a small bar in Perth (no plug, they don't really deserve it :P) that do this, using tablets as POS to provide table service. I was pretty impressed with how slick the whole thing was.
Don't think it really made much difference in the scheme of things but cool to see creative uses for newer technology. Bye bye pen and notebook.