I've spent a lot of time reading over the past few months. I hope I can save someone some time by sharing the best resources I found.
The Primal Blueprint (it goes without saying)--the whole lifestyle
Good Calories, Bad Calories by Gary Taubes--the most in-depth on the science
The Vegetarian Myth by Lierre Keith--very useful summary of diet science + bad news about the trajectory of humanity
The Protein Power Lifeplan by Drs. Eades--specifically, how to implement your diet. Has easy, medium & strict plans.
The Paleo Diet for Athletes by Cordain & Friel--if you're going to run 50 miles a week, you're going to need to top off those muscles with some carbs.
Body By Science by McGuff & Little--sounds too good to be true, but it's working for me.
PaleoNu http://www.paleonu.com/get-started/ --the whole diet on one page. Dr. Kurt Harris (a radiologist with an exhaustively researched nutrition hobby) answers questions in great detail, it's worth going through his whole comments section.
Marks Daily Apple Forum, obviously.
Dr. Michael Eades's blog: http://www.proteinpower.com/drmike/ --infrequently updated, but you can go through his archives and find all kinds of relevant discussion.
Theory to Practice http://theorytopractice.wordpress.com --good physiology & exercise science
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