Before i buy this new edition i was wondering what has changed from the original and if its an improvement?

The cards are full-sized so it takes a lot more room to play. However, the cards have text on them so you don't have to continually go back to the rules.

The original had one more copy each of Spoil Heap and Venomous Creeps (112 cards in the GW version, 110 in the FFG). Other than that, it appears to be the same.