The important bit with imitating a site like HN is not imitating the UI...but the UX. I don't visit this site for the page layout but because it loads 10x faster than every site trying to copy it. Don't implement loading animations, when the site is fast enough you won't see them anyway.

So basically the trick is to take a site like the new reddit.com, looking at it very carefully and then doing everything the opposite way.

(I think the overall design is fine though)