G'evening Terminus and welcome to the forums!

yes, you would need a license per machine... and those licenses are forever, and you get all updates for free.

of course... depending on your hardware... you may be able to use just 1 or 2 machines, and run multiple wows per machine.

until last weekend, i was running 5x wows on a single machine... an amd 3500+ 2.2GHz single core w/ 3g of memory and an 8800GT OC. i was driving 2 monitors and was able to get 5/25 fps outside of the big cities.

i hope that answers your questions. if you have more questions, please feel free to drop me a note.

have a great night,

Rob (keyclone developer)