This book is fantastic and a storyteller can get a lot of mileage out of this book. The four settings are very well written. Of course different people are going to like different settings (I'm a big fan of Gunstar Autochthonia and Burning Legend myself). So I think the best way to do this is to go through the different shards.
1 Gunstar Autochthonia: The primordials won. Exiling the Exalted host into space riding on Autochthon who is now a giant spaceship. Hounded by the new Infernal Exalted and shaken by the mysterious abyssals. This setting comes with a fantastically written charm set for the the Empyreal Chaos for antagonists or if you're feeling bold an Infernal game.
2 Heaven's Reach: Exalted in space!! A game set were a Lunar rules over a galactic empire controlling several systems. While the "Frontier" space is filled with mystery and adventure. As the Solar Exalted seem to be returning and gaining strength. Fills the need of the Scifi fantasy need in us.
3 Burning Legend: A more anime/manga take on exalted. The Exalted are not empowered by the gods but are fighters who channel their powers into devastating martial arts techniques. It feels very similar to Dragon Ball (not Z) or Fist of the North Star. This system is the most changed out of any of the others. Giving you different powers and making the entire game feel new and fresh.
4 Exalted Modern: Pretty straight forward. Creation is now modern. It's not our world with exalted in it. It is if Creation resembled our world. Familiar cities come up and and have a new modern twist. There are other major changes as well such as the Solars are just now appearing for the first time in History.
Finally the last chapter is filled with all sorts of goodies. This includes new charms for modern era Exalted and futuristic space settings. Weapons for each setting including guns, lasers, and bombs. It also comes with several setting hacks. Including Sidereal Astrology, Abyssal Resonance, Modern Alchemicals, and rules for Dramatic Chase scenes.