I want to invest in a few new books this year, and I am targetting the environmental line as well (I play 3.0, so books with too much character material like the Complete are off for me).
Let me check this one:
"The Dungeon as Enemy"
Sounds like very easy information: what feats & spells to take etc, you know it always ends up in obvious choices. Gamers like this kind of info because it tells you that you're good, since you have already figured these all out, but I'm too old.
New Standard Class: Factotum: hell no! I HATE characters that in a roleplay game want to cover everyone's roles!
"Tools of the trade"
Mundane stuff is nowadays more interesting to me than magic stuff and alchemical items also are never too many! Magic Items are not to discard, but I certainly don't buy a book because of these, they're everywhere.
"Character Options"
Totally useless for me.
"Dungeon Design"
Finally something solid for the DM! It's not truly necessary information here, but I think it'll make a good reading at least, to help design dungeons that make more sense to the players. This is IMO the core of this book.
"Dungeon encounters"
Samples... not useful for me. Totally unattractive templates. But the two new monsters could be salvageable, at least they are very dungeon-oriented without being the usual aberration.
"Traps"
Possibly great info here, depending on the actual implementation.
"Dungeon features"
Well nothing special, just dungeon dressing here.
In conclusion: 50% good, 25% questionable, 25% certainly useless.
It could be an "ok" book for me, but I'll decide after some review.