Чем отличается данный выпуск от оригинала???

Немногим.
Пропатчен. Плюс к этому...
...features
an all-new multiplayer mode, a new head-to-head deathmatch
mode, and a remixed soundtrack CD with more than 30 of the
best tunes from the game. Also included is a software
development kit, so you'll be able to create both single
and multiplayer missions from scratch, as well as modify
existing ones.

Практически все есть и без спец-версии