I tweeted about this new project a few weeks back but wanted to mention it here. One because it's a wonderful idea and I'm really excited to follow it's progress and two because one of the organizations you can volunteer for is the Brooklyn Museum. I wrote about their innovative community tagging program and it seems they are taking it further by soliciting tags from The Exraordinaries volunteers. Love it.
As for this whole idea of getting people to use their phones and little free time to do something good.....I also love it. I think if they can capture the spirit of playing a game it will really take off. Tons of people spend tons of hours playing little games on their phones, if you could play a "game" and do good, wouldn't that be great. It isn't really into the game realm yet but the potential is there.
There are quit a few community tagging/cataloging projects. What do you librarians think of this?
This one is pretty neat. Building a catalog of places for kids to play.