I don't know what special edition you're referring to there, cause there's 2 (kinda).
One of the special editions is slightly more expensive, but includes Divine Divinity. The other includes a 50 page Novella by Rhianna Pratchett.
Although neither are really "special" versions as such, since the UK version is the one with the novella, and it's just the normal BD game.
Tovi 
