  We report the results of a photometric and spectroscopic survey for planetary
nebulae (PNe) in the Local Group spiral galaxy M33. We use our sample of 152
PNe to derive an [O III] planetary nebula luminosity function (PNLF) distance
of (m-M)_0 = 24.86^+0.07-0.11 (0.94^+0.03-0.05 Mpc). Although this value is ~
15% larger than the galaxy's Cepheid distance, the discrepancy likely arises
from differing assumptions about the system's internal extinction. Our
photometry (which extends >3 mag down the PNLF), also reveals that the
faint-end of M33's PN luminosity function is non-monotonic, with an inflection
point ~2 mag below the PNLF cutoff. We argue that this feature is due to the
galaxy's large population of high core-mass planetaries, and that its amplitude
may eventually be useful as a diagnostic for studies of stellar populations.
  Fiber-coupled spectroscopy of 140 of the PN candidates confirms that M33's PN
population rotates along with the old disk, with a small asymmetric drift of \~
10km/s. Remarkably, the population's line-of-sight velocity dispersion varies
little over ~4 optical disk scale lengths, with sigma_{rad}~20km/s. We show
that this is due to a combination of factors, including a decline in the radial
component of the velocity ellipsoid at small galactocentric radii, and a
gradient in the ratio of the vertical to radial velocity dispersion. We use our
data to show that the mass scale length of M33's disk is ~2.3 times larger than
that of the system's IR luminosity and that the disk's V-band mass-to-light
ratio changes from M/L_V ~0.3 in the galaxy's inner regions to M/L_V ~2.0 at ~9
kpc. Models in which the dark matter is distributed in the plane of the galaxy
are excluded by our data. (abridged)
