I know I may be slow, but this is the first time I saw this. What an amazing event that I wish I could have witnessed first hand.
Imagine the effort that it took to get that going! Well, they actually showed a little of the rehearsal for the event the night before in another video. There is also a video showing the response to the event by those who seen it first hand. Kudos to T-Mobile in the UK for coming up with this idea.
Now for the crazy part of this. On You Tube there are quite a few jerks who would rather spout their hate and ignorance. I am amazed that there are people in this world that can't see the importance of doing these stunts. I understand that you may be frustrated, or may be against commercialism because it never worked for you. However, this took someones idea, the same persons effort to make it happen, and a whole bunch of people to do it. Everyone that was there was thoroughly entertained. People who watch this on You Tube is entertained (those who want to be anyway). Sometimes I wish I could tell people to go find a hobby that involves creativity. I have found it in music performance myself, and am able to enjoy other peoples creativity more in my opinion because I know how it is to make something for others to enjoy.
I guess this all goes back to an older post of mine in education of the Arts. Sad that people don't see things that way...