I just signed up to join Matt Harding the next time he comes dancing through Rome (... sadly I missed him for the 2012 video).
I can't ever pinpoint why, but this was always one of my favorite projects/ web phenomena. I find it incredibly touching to see the whole world dancing. It is like my favorite Disney World ride, "It's a small world after all."... I'm just mushy and idealistic that way, I guess.
Either way, it is brilliant to see all the ways people are making a difference (and a living) in this world! What an amazing job. Hope it inspires you as much as it does me!