Check again.
You're lucky I'm at the office in attempt to be productive.
But in actual response to the vid: It's awesome to see them having such a great time and is hilarious! I honestly don't think it has the slightest to do with substances as a lot of people seem to jokingly state on YouTube. I think these guys are just on a natural high in life. They have everything going for them with the upcoming success of their new album, excitement of a world tour, etc etc. Not to mention this particular lineup has perfect chemistry. I can only imagine that these guys all had a blast without a negative beat while in the studio and during promotion.