Hellfury said:
Occam's Razor. The FAQ states that when you have a choice, X is mutable, otherwise it's zero. You play Unspeakable Resurrection, and thus choose a target. Thus X is mutable. The fact that it's a different zone, or the fact you don't have to pay the cost you set is irrelevant. The FAQ doesn't mention zones.
It's that simple. The rest (like the older cards) is just evidence on how this conclusion holds up in a larger environment, but the simple facts are that UR works the same as normal, exept for the 2 changes Yog introduces: Playing it from the discard pile instead of your hand, and skipping the part where you pay the cost.
thats all I got.