Well, lovely singing and a great idea.

I don't like to be too picky, but the YouTube clip didn't do it justice. Pity it wasn't recorded by anyone who had any idea of how to use a video camera. I ended up feeling faintly queasy from all the snap-panning backwards and forwards. Plus half the time you couldn't see what was going on, as the auto-exposure control was working on the bright buildings and sky in the background and under-exposing the foreground.

Not to say the event itself wasn't a wonderful thing and the singing was great! More of this, please... Next time, a good photographer, and record the sound separately on a decent mic, though. And the "mob" should coalesce, so that their sound is coherent, rather than being spread out.