Without opening up the game, how do I tell from the box if it's a first or second edition? There is the possibility that this has been sitting on their shelf for some time.
I don't believe there's a way to tell from the box.
It's highly unlikely it's a 1st edition. That version was only out for a few months in 2008, and it was sold out everywhere. People were scouring every possible place looking for copies. Every copy since late 2008 has been the same, so even a 2 1/2 year old copy would still be the latest version.