Neuro, those are great shots, particularly that first one where the shape of the trees and the negative space really frames the bird. Were these hand held, or (I assume, at least at 1200mm) from a gimbal?
jrista, the 7D AF blows the old AF out of the water, but the 5DIII is definitely yet another big step up from the 7D, particularly with subject tracking. Being able to lock an AF point on a bird and have it track it over 2/3 of the frame is amazing. The 6FPS frame rate is a bit of a let down after the 7D, but is still fast enough to get good action shots most of the time, which is why I sold my 7D about 6 months after getting the 5DIII. The image quality, high ISO performance, and AF more than make up the FF and FPS loss.
I just had a 1D X delivered yesterday and haven't tried it out yet, but I'm excited, especially after looking at the 1D X photo thread and Neuro's shots above