I'm a big fan of Neal Stephenson (he's still my favorite author). Though I didn't enjoy his Baroque series as much as his earlier sci-fi like Cryptonomicon (favorite book) and Diamond Age, I decided to give his newest book (The Mongoliad) a try. (I'm still reading his other new book Reamde in parallel.)
I was a bit surprised that this book had so many co-authors listed, so I'm not sure how much of it Neal actually wrote. I didn't actually enjoy the book very much, and so I'm not sure if this is because it wasn't a lot of Neal's writing or because it was so much a mix of styles and opinions that the overall style got lost (or maybe I just wasn't into the subject matter as much).
After reading it, I discovered the book is sort of an experiment in crowd-sourced writing; check out mongoliad.com to see what I mean. I'm not sure if the community's stories were all incorporated or how that worked exactly, but it does seem like an interesting approach.
The book is about the era after Genghis Khan and features warriors and hunters and many, many vivid descriptions of fighting sequences (a bit too many for my taste -- might be more fun to watch as a movie). It features Mongolian spies, issues of court manners, and shows how women can often be much more sly and smarter than men in battle and in court. The issues of drunkenness, corruption, respect, and honor in battle played big roles in the book. Also, a lot of attention was given to horses, which played an important part in the story (and in history).
If you're into Western Martial Arts, horses, jousting, archery, or Mongolian era history, this book is for you. If you're more sci-fi/tech oriented, I would prioritize Neal's other books ahead of this one.