Well, I'll have to confess:

I'm inclined to be more of an encourager that a serious critiquer. I don't mind someone telling me how I can improve, so I'm not here just for strokes, but I always excel when people encourage me, so I have a tendency to tell them what I DO like about their photos, not what I find weak. That way they know they're on the right track.

That said, I have always found it a bit off-ticking that people seem to be in this just to develop groupies. Then they all say superlative things to one another about work that is really pretty bad; that way they all feel better. It's particularly upsetting when I see people put up an image that is really thought-provoking and visually compelling and they have at most one or two comments after being on the gallery for several hours, and, the section that shows "most commented" and "highest rated" or whatever have dross by the same names you always see -- some of which is fantastic, of course, but a lot of which is just cookie-cutter junk.

This has been cussed and discussed a number of times, and I don't see any of it changing as long as there are "most (fill-in-the-blank)" sections. As far as critiquing goes, I think a person should say what they feel and not be mean about it. If you don't wish to say anything negative, you shouldn't feel pushed to. If, on the other hand, you have some constructive criticism, I don't feel you should hold that back or be expected to either.

Just my .02.
John