I Am a Strange Loop by Douglas Hofstadter, is a much bigger, deeper, and altogether more involved book than The Moral Landscape. It has 24 chapters and an epilogue, it deals with difficult issues that Harris would likely dismiss as "boring". He sweeps across a wide range of very complex ideas including Incompleteness, Turing Machine, Neurobiology, Artificial Intelligence, and causality, not to mention brushing against many maddening ideas in contemporary Philosophy of Mind. I suspect I will sometimes need more than one entry for some of the chapters.
It has been pointed out that what I'm starting here can't really be called a "book review", rather, it is a commentary. For starters, I suggest glancing at the Wikipedia articles for some of the following if you are not familiar with these subjects: Philosophical Zombie, Qualia, and Goedel's Incompleteness Theorem. Finally, and rather idiosyncratically on my part, read the wikipedia article on Johann Fichte, try to grapple with section called "Central Theory", about the "I" -- I'm not a Fichtean, but it's an interesting read.