Some time ago I asked here whether or not the classical (\hbar \to 0)
limit of quantum theory agrees with classical mechanics. The answers
varied but a majority said yes. Recently I analyzed this question and
arrived at the conclusion that the answer is no. I wrote a paper on
that, see:
http://arxiv.org/abs/1201.0150, which may be of interest
to the members of this forum.
U.Klein