I quite like this. A lot, in fact. There's a wonderful sense of motion from the birds, of course, but I love how they're completely unaware of the manufactured world around them, or so it seems to me. And ignorant of the people on the right, who are also ignoring them. Really very calming and somehow uplifting.
What I liked about this was the magical waves of blurry white. Look almost like little angels. Glad you did not try and get a stop motion capture here - i think it would have killed some of the drama.
This is a great image. I'm going to get artsy and say that the longer exposure (and thus, them being blury) speaks to the evanescance and transiance of life.