The slides from the lastest talk on Gravi-weak unification theory can be found here with audio here. Previous coverage here.
In a nutshell, the argument is that the right handed side of the weak force (which operates only on left handed particles) is gravity. It predicts a sterile neutrino that could account for dark matter, a single Higgs boson and a graviton naturally. The asymmetric nature of the two forces is related to the cosmological constant. The forces share a coupling constant that is inserted in different ways in the respective equations. More conclusions based on the theory are expected to be forthcoming later this year. Dark matter particle interactions with each other are governed by a force with a mathematical structure similar to electromagnetism, i.e. U(1).