I converted image profile to sRGB for the web, then went through the essential adjustment layers, focusing on removing slight magenta cast (visible in sky) and the "hazy" feel in the tree background.
I also used the lens correction filter to straighten and distort the image, trying to reduce some of the "foreshortening" appearance that might be due to telephoto focal length.

forum discussion: http://forums.dpreview.com/forums/read.asp?forum=1006&message=26449244

original image by Jeffsphotos1: