The thing mentioned at Bonnaroo was nothing to do with Arcade Fire. It's a viral marketing campaign or an alternate reality game for something, and those floating blinking light things were posted out to anyone who registered at
Test Subjects Needed. They had a link to
Mission Icefly on them and that now leads to
Survival Code which has some video with the guy who played John in Lost talking about senses.
No information as to what it's advertising yet but people have suggested everything from Halo 4 to a new gum. I've kind of lost interest so if she really wants one I'll send mine out to her.