Site is a bit to 80's for my liking in it's inital appearence
The buttons on the right are not obvious for me
I think you need more white space between you comments as its a bit cluttered
I can't scroll down the page and see the contents of the ajax drop down.
I would make use of the face book like button and comments for my system and let your site better leverage social media
Using my mousewheel only is a bit strange, I can't tell if there are 10 articles, or 10 million...
The opened article seems to remain separate from it's title with the grey lines between them.
Graphics quality is excellent, colours are okay - I know you wanted them to be dark. I don't understand the flying "X" images at the top. Would these change as real posts re added?
Just a couple of things that struck me usability wise: -I found the design of the main article buttons a little confusing- as they look like one whole button my instinct is to click anywhere on the graphic for a iink- but only parts of this graphic link - I naturally tend to click on the words 'read more' as a iink as well rather than the circle -I know you say the dark is on purpose but for me i think a bit more colour variety and contrast would make a big difference