There were a few very minor changes between printings 1 and 2. All future printings will be identical to printing 2. The changes are:
1) Changed the box front to say 1-4 players instead of 2-4.
2) Fixed a small print error over the dwarf's head on the outside of the box bottom. Previously you can see the halfling's head behind him.
3) Added a sticker to the outside shrinkwrap with the Dice Tower Seal of Excellence on it.