The lines of light created by the falling water are terrific and your exposure is just perfect for it. Would you consider cropping off the top strip of the photo containing the background, I feel that it would add an abstract quality to the waterfall and increase its impact. But of course you are the author and you should present it as you wish.
Thanks for the comments, gentleman. Tex, I tried a crop as you suggested and didn't like the result. I don't really like the strip of background at the top either. I don't know what I'll do with this one.