  We consider the leading non-analytic temperature dependence of the specific
heat and temperature and momentum dependence of the spin susceptibility for two
dimensional fermionic systems with non-circular Fermi surfaces. We demonstrate
the crucial role played by Fermi surface curvature.
  For a Fermi surface with inflection points, we demonstrate that thermal
corrections to the uniform susceptibility in D=2 change from $\chi_{s} \propto
T$ to $\chi_{s} \propto T^{2/3}$ for generic inflection points, and to
$\chi_{s} \propto T^{1/2}$ for special inflection points along symmetry
directions. Errors in previous work are corrected. Application of the results
to $Sr_2RuO_4$ is given.
