That's a little scary and obviously annoying. Having said that, I am surprised at Visa's ruling.

I used an ATM in downtown HKG once and the same thing happened. After the PIN, no money but the card came out. It was a Sat evening so the bank was closed and I wasn't sure if it would open the next day. So I immediately called my bank and they assured me that the transaction was cancelled at source and there was no money exchanged at all.

I can only think to recommend that if it happens to anyone, STOP! Call your bank before you try again.