But are they HDR effects or just too much saturation?
In reality, it is the same thing, unless you actually shoot bracketed images and merge, most HDR effect programs amp up the Clarity, Saturation and Contrast. In Photoshop I create a new layer and edit in Topaz Adjust or Nik, then blend the result with an opacity adjustment to get the final look.
Nice idea - but the colour is way off for my eyes. Just doesn't look natural.
yeah, not natural, but sometimes natural can be boring. Actually, a beautiful scene like this does look really great as natural, but I like to see what can be done sometimes in a special way. The modern trend does seem to be toward more natural. And I am not really into things that are very abstract, but I do like to see what can be done to make things look a little more than natural. Nevertheless, both ways I think are very good. I just love the intensity of the colors here.