I think it is awesome! If you have watched the Olympics, numerous roofs in China have them. They look so pretty. I would love to do that. My only fear would be rot from the moisture. I am sure there is some way to protect though. visit www.greenroofs.com
Yup, I have one. It's great. My base temperature stays pretty constant. In the winter it's around 55, still need a bit of heat, but not too much. In the summer, 75. With a fan going it's great. Get some warm days but nothing too unbearable with outside temps soaring in the high 90s. last winter it was 23 outside, no clouds and sunny so inside rose to near 80 with no heat. I love it. I'm still in the process of figuring out plants for my roof. bought some native wildflower seed to be planted this fall. Once I get it up and going, I'll post photos.