Okay, I completely understand that the Heisenberg Uncertainty principle is simply the manifestation of the fact that observations are fundamentally interactions.

However, I never thought of the uncertainty principle as the part of quantum mechanics that causes some interpretations to treat observers as special. I was always under the impression that it was quantum entanglement... I'm trying to imagine how a purely wave-function based interpretation of quantum entanglement would behave... what is the "interaction" that localizes the spin wavefunction, and why does it seem to act across distances faster than light? Please, someone help me out here.