a 'computing environment' is not Turing Complete, but computer languages are.
So? Ethereum is turing complete then. Running out of ether is part of the environment, not the language.
this poses the first problem of FALSE ADVERTISING. These aren't turning complete scripts, it's just a bloated up dispatching environment for financial transactions. I think they're overestimating how 'cool' this is going to be. It's not going to be fun to make or to use.
Yes, this is what I think is the real problem, programs are hard to understand and debug.
In law, sure judges are nondeterministic, but they don't do totally insane stuff, like in a parental custody hearing, they don't set their program counter to the wrong number and accidentally sentence some innocent bystander to death. Something that bizarre could maybe happen in ethereum.
Still, I am not sure if this is a fatal flaw, if anything it might limit scripts to what is easily comprehendable by one programmer. That's still a lot more flexible than bitcoin's scripting system.
I don't really care how they sandbox their environment, in theory it should be a lot simpler than the JVM. But maybe it is easier to just use the JVM and lock down everything except the few resources ethereum needs access to. Either way, the sandbox is not going to be what holds them back, I think those already exist and are a proven concept.