>>3
It is deterministic, but we cannot observer it's deterministic nature directly. We can only philosophize about the nature of the wave function collapse. At least at this moment.
Many worlds for example, plunges determinism right back into quantum mechanics and it could be proved or disproved. So nothing is lost yet. Interesting enough, there is a wave function in this theory, which describes the complete state of the universe, this wave function is deterministic at all times, because there is no one to observe it. The super positions are the different universes.
But even then, the probabilities
are deterministic, so even if the Copenhagen interpretation is the right one, a certain level of determinism is still obtained.
The relational interpretation is also interesting, there the state of the system describes the relation between the observer and the system. Thus a different observer could come to a different (but even so) correct answer.