Looking forward to when the full version of this comes out. Huge fan of 1001 Nights, currently running my own homebrew desert setting based in part on Al Qadim, in part off Dark Sun, a bit of Dune thrown in, and my own experiences living in the Middle East first hand. This book reminds me some of that, and I get a feeling of comfort and home from it.
The races are interesting, reading over the playtest rules, the classes are pretty spiffy, and I cannot wait to find out more about the 101 Nights of Wonder, and how they could play into various plot points in games and whatnot.
All in all, solid book.