For anyone who has read the first book (like me), know that this one is a vastly better than the Disgaea 1 Character Collection. Media Works seemed to have listened to their fans regarding the first book (which had a bit too much data) and filled this to the brim with artwork.
The book goes in this order: Promotional artwork, In-game artwork, Weapon sketches, Movie storyboards, Location guide (mainly background CGs), Character guides and sketches, Concept art, Ending guide, Item list, Skill list, Interviews, Anime Guide, and some ads for other Disgaea products.
Most the sections that before had charts and tables have been cut down to friendlier comments and notes.
Bottom line: If you love Disgaea or have any interest in it whatsoever, get this book.
P.S. I don't know if the offer still stands at the time you're reading this review, but (perhaps) at Nippon Ichi's shop site, Rosenqueen.com/home.php, they're offering this book at the MSRP of $19.99 with an additional bonus of three Disgaea 2 pencilboards (strangely enough, one of the artworks on them isn't in the artbook?).