The band were rehearsing at Toronto's Air Canada Centre until late last night.
When Bono arrived back from speaking at the premiere of the Leonard Cohen film, the band were soon on stage and running through the set.
Far be it from us to give away any trade secrets ahead of showtime but let's just say that those inside the arena last night got to hear several songs that have not been aired on the tour to date. Surprise tracks included at least two from 'All That You Can't Leave Behind'. Will they feature in tonight's show ? Have to wait and see.
It also looks like some of the lighting and visual innovations we saw in the European stadium shows have made their way back across the Atlantic - the show will not be a carbon copy of the opening North America leg last Spring.
More news from here in Toronto later in the day!