eiii: Actually none of the Divinity: Original Sin packages on GOG is a good deal. Either you get an incomplete package with no upgrade path or you have to pay a lot of money for unwanted bonus codes.
Geralt_of_Rivia: And what exactly is missing from it? The only thing I've found from the description is the artbook and the soundtrack or is there more I've missed?
That is also the conclusion I reached, so unless you really want the artbook and soundtrack, then you are better off getting it now on sale. What I like about the collector's edition is the extra copy of the game, which is a great bundle for a co-op game.