When the new team took over development on HN, we decided that before we implement any new frontend features for the site we needed to update the markup HN uses to make it easier to implement such features in the future (just the markup, not the aesthetics).
Creating a visually identical version of HN with CSS3/HTML5 was easy (we also made it responsive to work on mobile devices)--implementing it was another matter. HN's presentation layer is heavily intertwined with the application/server logic, which meant it was going to be a bit tricky to separate the two. The reason it was tricky is because the entire code base up to a few months ago was optimized to be worked on by one person, pg. For example, we didn't even have docs on how to setup / run the arc code on local / development machines when we first got started.
Eventually we did get a version of HN working that's separated the presentation logic, but we realized that MANY of you out there have built apps that rely on scraping HN's outdated table markup. Because we decided that it would be bad to break all of your apps overnight, we've now started working on an API for HN to launch it in tandem with the new markup changes. We'd then give you all some time to update your projects.
Please try to keep in mind that new features for HN have to be done alongside a lot of other responsibilities. The software team that works on HN is also spending time moderating it and rewriting software that runs YC. Some members like Garry and myself divide our time between developing for HN and our duties as partners helping YC's startups.
This is a long-winded way of saying, please be patient. We are working on many shiny new things for you and can't wait to show you what we've been building behind the scenes. Until then, we're delighted to see implementations by HN users like sagargv. Hopefully, we'll be able to reduce the reasons for you to spend time on projects like these soon. :)
Edit: Was viewing this out of context - there is another mention of HNES up top, I apologize for the repetition.