I have CS2 and used mostly the healing brush and soft brush to get rid of the branch. There are many repeating patterns in a bird's wing feathers and the trick is to pick the right part of the pattern to replace the missing parts(because of the branch) and to not let up on the brush so you replace a larger part of the pattern.Some smudging also helps.Removing the branches from the sky background is a snap.
The beak I took from another picture after using quick mask to refine my selection.I resized(transformed in CS2 jargon) the beak and warped it slightly to get the correct angle.I had to replace the bluish color in the beak to gray also.The beak is a little too bright to my eye and I need to tone down the highlight refections a bit.
As a quick fix I just now processed the photo to add some fill light in the wing shadow area and the print looks acceptable.However, I don't think it will ever be a stunner. You can take a great photo and make it spectacular in PS but you can't ever make an average photo spectacular.
In my mind a good bird photo requires correct light,tack sharp focus,sneaking close,and luck to capture the right millisecond of action.This photo simply lacks the good light and a bit of closeness(besides the branch I started with).Its also not as sharp as I like.