Slobodan,
How does one discuss technical and aesthetic issues without offering a critique?
Example:
User Critique - I might say, referring to a particular image, something like: "Dodge here, burn there, crop, adjust this or that, etc."
This forum - we might discuss "technical and aesthetic issues" in more general terms, e.g., how appropriate photoshopping is for landscape photography, without referring to a specific photograph, or perhaps using it as a starting point.
People who want to hear a critique of their work and perhaps hope to benefit from advice there, will post in User Critique. Those who do not feel so and just want to display their work will post in this forum.
I personally post mostly in the User Critique forum for two reasons: 1. I oftentimes am interested in how others perceive my work, especially if I am playing with something new and 2. Given that I often critique others' works (which sometimes is not received well), I feel it is only fair to expose mine to the same treatment.