  We have used asteroseismology to determine fundamental properties for 66
Kepler planet-candidate host stars, with typical uncertainties of 3% and 7% in
radius and mass, respectively. The results include new asteroseismic solutions
for four host stars with confirmed planets (Kepler-4, Kepler-14, Kepler-23 and
Kepler-25) and increase the total number of Kepler host stars with
asteroseismic solutions to 77. A comparison with stellar properties in the
planet-candidate catalog by Batalha et al. shows that radii for subgiants and
giants obtained from spectroscopic follow-up are systematically too low by up
to a factor of 1.5, while the properties for unevolved stars are in good
agreement. We furthermore apply asteroseismology to confirm that a large
majority of cool main-sequence hosts are indeed dwarfs and not misclassified
giants. Using the revised stellar properties, we recalculate the radii for 107
planet candidates in our sample, and comment on candidates for which the radii
change from a previously giant-planet/brown-dwarf/stellar regime to a
sub-Jupiter size, or vice versa. A comparison of stellar densities from
asteroseismology with densities derived from transit models in Batalha et al.
assuming circular orbits shows significant disagreement for more than half of
the sample due to systematics in the modeled impact parameters, or due to
planet candidates which may be in eccentric orbits. Finally, we investigate
tentative correlations between host-star masses and planet candidate radii,
orbital periods, and multiplicity, but caution that these results may be
influenced by the small sample size and detection biases.
