I despise it, for the most part, because even though it can be used to capture a scene as it was seen by the eyes instead of based on the limits of the medium, it is most often used as a cheat, or as a way of creating a new reality. I'm a believer in realistic photography, and I think HDR is crack for photogs. Like when you have a hammer and everything begins to look like a nail, with HDR, everything starts to look like an HDR situation.
With waterfall photography, it is WAY overdone, especially by the Flickr crowd. Some people do it well, but most do it very poorly, and end up making photos that are, too me, unappealing because I know they aren't "real" anymore.
That said, I know of a few places that would be best captured in properly executed HDR. I don't currently use it, but I wouldn't totally rule it out, because as I said, it does allow you to get around a few technological limitations inherant in film/digital image capture.
Edit to Edit: I was mistaken.
Edit: I think BamaWester on Flickr uses HDR sometimes, but it is almost impossible to distinguish his HDR and non-HDR pictures because he has a knack for good lighting. The only good HDR is invisible HDR. http://www.flickr.com/photos/bamawester/
