I have heard this song before, but I really heard it for the first time at my cousin's wedding this weekend.  I think it's a pretty emotionally charged song, and not just for the hyper-happy sing-song-y nature of the tune.  I've checked out several live versions of the band playing this and they bring the same wanna-get-up-and-dance-around infection every time they play it.  But nothing could compare to the dancing disease that was going around at the wedding on Saturday night in a barn in Iowa.  I hesitate to to use the word, but it was fucking magical.