Baldur's Gate II Collectors Edition on the outside looks like a fairly standard game - the only thing that sets it apart from the classic box, is a yellow-gold oval on the front of the box that reads "Collector's Edition" and a number on the back.
Classically, the words "Collector's Edition" on the front of the box means that there is a toy or something thrown into the box as a marketing ploy (this can be seen with the "collectible" boxes and manual covers for Warcraft III). However, for some reason BGII actually adds more functionality to the game - this is slightly annoying to people who both want to collect the game and keep it in its shrink wrapped package and at the same time play the game.
On the back of the box is a sticker that indicates what number out of the 62,000 made yours is. Inside the box there are:
It is this bonus CD that makes the collectors edition worth what it is. This CD has art, portraits, music tracks, and a complete walk-through for the first chapter and an additional merchant in the game named Deidre.
Deidre shows up in the Adventurer's Mart along the Waukeen Promenade who has several magic items from the Planescape: Torment game for sale priced in the "you can get that much money?!" range (from 20,000 gold to 50,000 gold).
The Collectors Edition is only available for the Windows platform, though the bonus CD that came with it was available for Macintosh if the game was pre-ordered through MacPlay - it does not come as part of the standard game for Macintosh.
http://www.gamezone.com/gzreviews/r15919.htm
http://www.onepc.net/reviews/0017/