This is another one of those songs that I always seem to hear when I'm in Paris; and it has the virtue of being the song that finally convinced me that you really never needed to learn the "nous" conjugations of verbs, because you can always use "on" for first person plural.
And the best lyric of the day "we will all be in heaven, even me!" (on ira tous au paradise, meme moi) What a cheering sentiment.
The crowd here is infectious. I know that they handed out sheets with the song lyrics on them earlier in the day (long before dark). But wouldn't you love to be lost in the middle of the madness?