Here we have some answers from Robert Schwalb on the GR Boards:
Basically, each chapter serves as a mini-Races of Renown Book. Basic format went as follows:
Intro
Playing Races
Race Variants
Race Feats
Race PrC
Race Spells
Race Equipment
The exception is in the Other Races chapter, where we updated a several races from Bastards & Bloodlines, a surprise or two from Jade Dragons, some races from Aasimar & Tiefling, and a few new ones.
The basic idea behind this book is to make your racial choice more important. As written, a character's race selection is important for about the first 5 levels or so (with the exception of a few racial PrCs and the very rare racial oriented magic item). So, b/c it's constructed with this in mind, everything inside emphasizes character options regardless of the level of play (translation: epic advancement for PrCs).
Another decision I had to make was whether to keep some of racial cultural information touched on in say Wrath & Rage and Hammer & Helm. B/c space was at a premium, I opted to leave that stuff out, so you could use this book in any game (from Greyhawk to Freeport).
From the outset, this is a rules heavy book, but not unbalancing. Also, there are no crummy feats (none of those dreaded +2 bonus to two skill feats). Prestige classes are challenging to enter, but offer lots of cool benefits. There's just a ridiculous number of spells too.
Specific Answers
Other Races: Specifically, you'll see stuff like the Trixie, Cambion, Nephilim, and the dragontouched.
Elf: All MM subraces are described and given a little more flesh than the 1 p description in the MM.
Oh, and you can use this book in conjuction with the APM, AB, AGG or alone.
I'll spill a bit more as we get closer to the release.
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