Wonderful! I love the music too. This is a very nicely done Flash animation. I like the designs, the colors, that you kept things simple. Too many people do Flash animations and get carried away trying to be fancy.
Aw no, I'm glad you got some emotion out of it! Depicting emotion is tougher for me in Flash. If I had more time I could have made a color key for this and brought out the emotions of the scenes more.
In my mind the beginning stages should look sunny and optimistic, then the middle-aged tree should look venerable and full of animals, and the winter-themed part of it should look more perilous. Then spring returns in full force for a happy ending.