The XL edition comes with the GT5 game and all of the free updates released so far, including the Spec II update. In addition, it comes with a code that allows the buyer to download an additional $20 of Gran Turismo 5 content, including the Racing Car Pack, Car Pack 2, Courses Pack, Racing Gear Pack, and the Paint Pack.
The best news is that the entire package will only cost those in North America $39.99 when it drops. Currently, we have no word yet on whether it will makes its way into the European region; we suspect that it will at some point but it is more of a question of when, our sources tell us.