From the economist
my comments in bold italics
A provocative quote comes from one of the top scholars of Behavioral Finance. In this quote he actually endorses the "weak form" of the efficient market theory which is actually the one most relevant to individual investors (my bold)
Yet EMH-ers and behaviouralists are increasingly asking the same questions and drawing on each other’s ideas. For instance, Mr Thaler concedes that in some ways the events of the past couple of years have strengthened the EMH. The hypothesis has two parts, he says: the “no-free-lunch part and the price-is-right part, and if anything the first part has been strengthened as we have learned that some investment strategies are riskier than they look and it really is difficult to beat the market.” The idea that the market price is the right price, however, has been badly dented.
For those looking for a more detailed more academic view of the issues take a look at the article by Prof Andrew Lo (MIT).
In fact for those with an academic bent look at pretty much anything he has written. He is even open to the academic heresy that technical analysts have something to say. As the title of the book states most academics view them as The Heretics of Finance.