For myself, I enjoy looking through the images posted - if I have time - and I do have an opinion good, bad or indifferent. My replies tend to be with images that have a strong visual impact to me and hold my interest. There are many genres of photography that I simply am not interested in. The works may be very good. I personally am not one who just says nice picture for no particular reason. Something I have learned from the school of hard knocks is that I will not express a personal opinion on an image (or try not to) that is anything other than favourable - whether the person posting agrees to critiques or not. I enjoy posting my images, knowing there may be some who enjoy looking at them or who may benefit from seeing my way of shooting. And I also know there will be people who don’t like or appreciate my style of photography. That is how I use forums, so that is fine. I really don’t expect comments or rely on others opinions to give credibility to my work. I do accept that other photographers do post their images for the feedback though. It is nice if they are able to get that.