[jaibot]

I routinely pay for things with ethereum - and if the target only accepts btc, then I can just shapeshift.

The "Halting Problem" is a red herring here - eth transactions are technically not Turing complete since they automatically halt when they run out of the finite supply of ether attached to the transaction. Saying that ethereum isn't feasible because of the halting problem is like saying cars aren't feasible because an object in motion stays in motion - there are countless practical ways to manage it, and if nothing else stops you, in the end you'll definitely run out of gas.

[mikejarema]

Here (and when I see people generally using the term) is the meaning of "shapeshift" simply that you go to shapeshift.io and exchange from one cryptocurrency to another?

[jaibot]

Yup!