On top of this, the eye tends to move from top left to bottom right. This grid layout forces the user to read left to right across the entire screen, drop down

On top of this, the eye tends to move from top left to bottom right. This grid layout forces the user to read left to right across the entire screen, drop down and start again in an unnatural way. The problem is amplified when scrolling. I would suggest moving towards a standard top down list (ironically like the existing HN). I would avoid using screen grabs, as HN articles tend to be about written content.