I wanted to play with your file, but when I tried to download it I selected to "run" it rather than "save" it, and therefore lost it (or at least cannot find it). I then tried to re-download it, but it had exceeded the number of downloads. If you do not mind re-sending it, I can try again.
Ok - I gave this a shot. I had to convert the file to DNG format so CS3 could read it.
I brought in two different exposures settings from ACR and blended them in PS.... Now that I am looking at it from the internet, I am not sure I like the top of the mountain in this shot. This was a pretty quick adjustment, but this is what I have.
I have been playing with a demo version of Photomatrix, so thought I would try that with your file. I saved three different exposure setting in ACR, and imported those three files into Photomatrix, then played with it a little in both Photomatrix and PS. I thought it would be interesting to see the difference. I think I like what Photomatrix did to the trees better than the other version.
You can see it has the photomatrix watermark because I do not think I will purchase the software; I am only using the demo.
Hope this is helpful - thanks for letting me play with it.
Yes - I see there is some banding in the sky in my version. I am not sure why - but somewhere in my process I think I added that. I played with it a little bit below again; while it is a little better, I did not eliminate it and now have some ghosting. Sorry I think that is beyond my current PP abilities.