I assumed it would be worse technically. Perhaps if it was OK to relentlessly poll, it could be a good service. Things like votes and comment edits would be hard to capture quickly unless every single item was relentlessly polled.

On the other hand I am not trying to rule out viable alternatives by suggesting it comes straight from HN, I even considered making what you are saying at one time. I just don't think it would be as good as an HN one.

I was thinking the same thing a while back. An API for HN would be awesome. A problem with that though is that it is really only a one way street and only allows for passive consumption rather than easily interacting. While a site-scraper API implementation would be handy, I think people would lose out on the functionality and community interactions that can only really be had at news.ycombinator.com.

Still though, I suppose some sort of site-scraped data (perhaps hosted on google apps for everyone to use) could be used in tandem with a greasemonkey script to further enhance the site without taking away the interactivity, that could be interesting...