Electroweak Baryogenesis: An Overview (Where are We Now?)
  It now seems plausible that the observed baryon asymmetry may have been produced at the electroweak phase transition. We review the considerations which lead to this conclusion, focusing on the obstacles to making reliable estimates. These arise from incomplete knowledge of baryon-violating rates near the phase transition, our limited understanding of the phase transition itself, and incomplete understanding of the mechanisms which actually lead to an asymmetry. 
Michael Dine