Professor Aswath Damodaran (Stern School of Business, New York) updated his article Equity Risk Premiums (ERP): Determinants, Estimation and Implications to include data through the end of 2009.  In the article, he investigates:

the three basic approaches used to estimate equity risk premiums – the survey approach, where investors or managers are asked to provide estimates of the equity risk premium for the future, the historical return approach, where the premium is based upon how well equities have done in the past and the implied approach, where we use future cash flows or observed bond default spreads to estimate the current equity risk premium.

The 2010 edition of the article is available here.

Aswath is also running a two-day NYU executive seminar on valuation every year at the Stern School of Business at NYU. This year the seminar will be on June 21 and 22. Click here for more information.