Think Seaworld in Orlando Florida 2010. It's their Sea of Trees. You can read details about it in the December issue of PlanetChristmas magazine at http://www.planetchristmas.com/magazine/December2010/index.html#/14/
This video isn't the best. Jump a few inutes into it to see the trees work their magic.
>125K LEDs... each is individually programmable and can be any color of the rainbow.