  In a recent article (New Journal of Physics 9, 165, 2007), Wiseman has
proposed the use of so-called weak measurements for the determination of the
velocity of a quantum particle at a given position, and has shown that
according to quantum mechanics the result of such a procedure is the Bohmian
velocity of the particle. Although Bohmian mechanics is empirically equivalent
to variants based on velocity formulas different from the Bohmian one, and
although it has been proven that the velocity in Bohmian mechanics is not
measurable, we argue here for the somewhat paradoxical conclusion that
Wiseman's weak measurement procedure indeed constitutes a genuine measurement
of velocity in Bohmian mechanics. We reconcile the apparent contradictions and
elaborate on some of the different senses of measurement at play here.
