He's a California based psychiatrist who also happens to write rational fiction (reddit.com/r/rational) and has interesting blog posts. I don't think he has any special qualifications or status that would make his review any more authoritative than anyone else's, but I really enjoy his writing style.
He is a pseudonymous blogger who has been described as one of the most influential bloggers by more than a few other very influential bloggers.
If you wish to know more, I'd nominate "Who by very slow decay" [1] as his one work that everyone should read, because more people knowing it would make the world a better place. (edit: content warning: hospitals and death. It's not a pleasant read, but I think it's a necessary one.)