The Supernova Legacy Survey (SNLS) has completed the first two years of its five-year program and cosmology results from the first year are in press. This unprecedented data set is ripe to begin examining the properties of Type Ia Supernovae (SNe Ia) with the aim of shedding light on their properties as standard candles and refining their use as cosmological probes. I have begun a study of the rate density of SNe Ia in the redshift range 0.2 < z < 0.6 and, after a brief review of the cosmology results, will present a description of this study. I will review some recent models connecting cosmic star formation history with the observed SN Ia rate density evolution. Now that our samples in various redshift bins are getting large and as a result, statistical errors are getting small, the dominant factor preventing a meaningful distinction between models is survey systematics. I will describe how SNLS will help to control these systematics and begin narrowing in on the progenitor population of SNe Ia.