Lets accept it – even the most advanced camera available today is not capable of mimicking human eye. Many a times I have seen some wonderful scene and wished that I could just capture it just like my eyes see it… If I have a camera, I take a shot. But, somehow it never turns out to be satisfactory. (Not a surprice, because I am no photography expert.). When that photo is given a retouch using Photoshop or GIMP, its amazing to see the transformation. I can change the white balance, sharpen it, change the tone, change the color of my shirt, can fade disturbing backgrounds, change backgrounds, and even warp objects!!
A photographer doesn’t have all the time in the world when he clicks a photo. And there’s a limit to what he can do with his camera. For example, consider HDR (High Dynamic Range) imaging – even the best DSLR can’t produce it. But our eyes perceive real world in HDR. Check this out: http://www.smashingmagazine.com/2008/03/10/35-fantastic-hdr-pictures/. Similarly, if you check out the best photos in flickr, you can see that almost all of them are post-processed to achieve the best effects. Post-processing is not evil 
Have a look at the result of some simple post-processing steps: (sharpening + blur + level adjustment)
So, what I expect from a camera is not fancy effects – but its real capability to capture details. Effects are best handled by computers. Once a detailed picture is available, it can be transformed into stunning one using post-processing. Well, even if you have just a point-and-shoot camera, post-processing can do wonders…
Most of the model photos are either the result of a costly equipments and a world-class photographer, or the result of professional post-processing. The latter is more common. Post-processing helps you make a bad photograph good, and a good photograph great!
