Setup. Nikon D700, 300mm f2.8, 1.4tc, tripod. 1/60, f5.6, ISO 640. WB, EX adjusted in acr, S/H, color, lightened eye, select sharpening of perch, some darkening of parts of BG, usm in cs3.
Very nice image! Bird looks great and the perch is really fantastic! Not crazy about the bright areas at the BG but if this is not a setup I guess there wasn't much you could do about it.
I do not think you could have processed this image any better, it is tack sharp with beautiful detail and color.
The circles in the background do take away from this otherwise superb image.