Nice shot, great timing.
I'd have preferred it at a wider FoV - not cutting off those extending wings. Looks a bit backfocused, and probably a little more DoF would have been good as well.
Not sure if it's a new Flickr thing (compression), or something about the post processing, but the full size image has an almost oil-on-canvas-filter look that my T1i images didn't have. I see it even on the in-focus regions, so I'd guess it's not a 100-400L bokeh issue.
Looking forward to seeing more!