This was discussed a while backdiscussed a while back, and the general consensus was that you could post a picture to illustrate a specific question about it (For example, if you were asking how to take a product shot and make the background transparent, without losing the shadows); But this isn't the place to post your pictures with vague or subjective question like "Is this composed correctly?" or "what do you think of this?".
The is a general chat room associated to the site, which has seen people swapping links to their Flickr profiles (etc.) and swapping opinions on pictures.
