Inhomogeneities as a bias and as a probe

Precision Cosmology requires us to take into account the small scale inhomogeneities in the Universe when discussing cosmology. I will discuss the effect of small scale inhomogeneities on the luminosity distance - redshift relation within LCDM:
1) How inhomogeneities bias the Hubble parameter due to peculiar velocities.
2) How inhomogeneities serve as a probe of the primordial power spectrum on small scales through the lensing dispersion of Type Ia Supernovae.