I've seen Aaron do this song and this is how he plays the intro.  
You'll just have to figure out the syncopated rhythm. 
 
 
He starts playing a "G" and hammers on the D and B strings. 
 
 
E-----3-----------3 
A-----0-----------0 
D-----0-----------2 
G-----0-----------0 
B-----0-----------1 
E-----3-----------3 
 
 
Of course you can also play G like this.either way sounds fine, 
but when I saw Aaron play the song it looked like he did the first example. 
 
E-----3 
A-----2 
D-----0 
G-----0 
B-----0 
E-----3