Chapter by Chapter breakdown:
Chapter I: Species:
New species include Dug, Gen'Dai, Iktochi, Kaleesh, Kaminoan, Kerkoiden, Nautolan, Nelvaanian, and Vurk
Some really great species here that have been missing for too long; most notably the Iktochi, Kaleesh, and Nautolan. Gen'Dai is a little bit overpowered in my personal opinion, and I would be hesitant to let a player make one.
Chapter II: Heroic Traits
Every base class receives new talents, most notably a couple that allow you to gain and command followers. Unfortunately, Jedi and Scoundrels are left out on the follower love here. I think the real reason is because they're going to put Jedi followers in the upcoming Jedi Academy book, but its still disappointing. In my opinion, the coolest talents belong to the new soldier tree: Trooper. Really awesome stuff.
There's a lot of new feats here also, with a little bit of something for everyone.
Chapter III: Prestige Classes
Ace Pilot, Elite Trooper, Force Adept, Gunslinger, Jedi Knight and Officer all get new talents. Elite trooper and Jedi Knight get entirely new trees (Melee Specialist Republic Commando for ET, and Jedi Archivist and Jedi Healer for JK). I have mixed feelings on these new trees. Melee Specialist would have been better suited for the Melee Duelist PrC that was introduced in the KoTOR book. Republic Commando is really cool, as is Jedi Archivist, but Jedi Healer really steps on the toes of Force Adept. I mean FA arguably doesn't have much going for it already, and now Jedi Knight has one of their best talents (Force Treatment).
Three new prestige classes: Droid Commander, Military Engineer, and Vanguard. At first I thought Droid Commander should have just been an Officer tree, but their class ability is actually really unique and useful. Military Engineer should have just been combined with The Force Unleashed's Saboteur for a Tech Specialist prestige class. Vanguard is a unique concept, but I think that a lot of the talents are fairly weak for a prestige class and it probably could have functioned as a Scout tree.
Lots of new Force Powers here (Cloak, Levitate, Malacia, Morichro, Phase, Rend, Shatterpoint, and Technometry). Some of these are really cool, specifically Cloak, Phase, and Technometry. I think that Shatterpoint is somewhat overpowered (potentially dropping a target's damage threshold down 20 points)while Rend (which deals 3d6 damage, 5d6 with a force point) is really weak. Theres a whole bunch of new force talents, techniques, and secrets, as well as three new Force Tradition trees.
Chapter V: Equipment and Droids
Lots and lots of weapons and droids. The coolest thing here, in my opinion, is Vibroknucklers and new Wrist Rocket ammo.
Chapter VI: Starships
A couple of new ships here, only one of which gets a deckplan (the Barloz-class freighter). It's actually a pretty cool ship, and fairly affordable, and I think my players will be purchasing one as their first vessel.
Chapter VII: Clone Wars Campaigns
This is where the book gets awesome in my opinion. There's lot's of advice on how to capture the feel of the Clone Wars through subtle details, as well as rules for Mass Combat (which are simplified, though extremely effective). There's also a sidebar on playing as a Clone, which has embarrassingly bad stats, 21 point buy I think :[.
Chapter VIII: Galactic Gazetteer
Updated Information for all the planets, as well as several new ones. These chapters tend to bore me. Moving on.
Chapter IX: The Jedi
After about five pages of fluff on the Jedi Service Corps and the various Jedi Councils, this chapter dives straight into predominantly stat blocks. There's the obvious guys (Anakin, Obi-Wan, Mace Windu, etc.) and a few cooler ones (Aayla Secura, Saesee Tiin, Quinlan Vos). The chapter ends with a few Jedi-oriented starfighters.
Chapter X: The Republic
This is a really great chapter with tons of valuable information to give a sense of authenticity to your Clone Wars campaigns. It details a lot of the bureaucratic inner workings of the Republic, even going so far as to give the colors for Clone ranks. Then the necessary stat blocks and lots and lots of vehicles. Most of which are awesome.
Chapter XI: The Confederacy
Same general layout as the Republic chapter, detailing the different factions of the Separatists and then lots of droids and vehicles.
Chapter XII: The Fringe
Really really short chapter.We're talking under ten pages. Just a few stat blocks (young Boba Fett, Chewie, a few others) and some vehicles.
Overall, this is an awesome book but it's got a lot more fluff than previous supplements. The mass combat rules are invaluable to any era really, but you might want to consider how much you're willing to spend on those rules before you buy this. Almost the entire book is very Clone Wars specific and unless you're playing in that era (or an era very close to, such as the Dark Times or Rebellion), you're probably only going to be using four or so chapters of this book.