I picked up my copy last night. It is pretty good. It doesn't add much new for the classic races except roleplaying and cultural aids but it provides a LOT of new stuff for the Kalashtar, the Shifters, the Warforged and the Changelings. I am at work now so I will elaborate as best I can from what I remember.
The other races; Elves (Valinar, Khorvaire, Aerenal, drow), Dwarves, Half-orcs, Halflings, Half-elves, and gnomes each get a couple of pages in the book on how the race operates in the Eberron setting. Each also has roleplaying tips.
Unusual Races: Goblins, Orcs, the Inspired each also get a couple of pages of write up on their culture.
New Feats: Lots and lots. Shifters alone have about 14 feats (they also have a couple of new shifter-types - one that gains bat-like wings, one that swims and one that grows horns and can deliver a 2d6+str gore attack). Warforged gain a couple of new feats including one that grants them a wooden body so they can become druids. There are even additional feats for the common races (many are quite powerful) and additional psionic feats as well.
New PrCs: I think there were about 8 of these. I didn't look too closely at them last night. I think there was about 2 for each of the new races (kalashatar, changeling, warforged, shifter). I only remember the 2 warforged classes. 1 was a 3 level class where the warforged tries to become more in tune with his living side. The second warforged class is sort of similar to the tattooed monk from Complete Warrior. It allows the warforged to access runes carged into the warforged's body for supernatural effects. I didn't have time to look closely at the others.
Substitution Levels: I didn't look too closely at these either but as I recall the new races each have some. The warforged artificer gains to ability to make a weapon into his familiar and to get double value out of the xp in his craft pool. The warforged paladin gains the ability to heal constructs and smite constructs. The warforged fighter gained d12 HD and some other abilities that I can't remember.
If people have any questions I will answer as best I can.
Tzarevitch