This is cool, but you really should have used bar charts rather than pie charts. Humans are really good at comparing lengths, and terrible at comparing areas. As an example, your chart of which database systems HNers use is almost meaningless to me - it conveys less information than staring at the raw data does. If you were able to rewrite to use bar charts instead, this would be a kick-ass tool.
The results of the first poll I looked at surprised me and I wanted to read the comments, so I think it would be useful to have a link to the actual poll (on HN) because I had to google it.
Another small thing is that the "HN Charts" in the nav bar doesn't really behave as expected. For example, on that page : http://hnlike.com/hncharts/chart/?id=3298905 the link doesn't do anything. On other pages it brings you back to the home page.
I must admit I don't fully get his argument. Is there research into the perception of pie charts, or is it just an assumption that people are bad at judging areas and angles?
I'm not a web developer, so maybe I'm misremembering, but wasn't there something in HTTP that let you check the last time a page changed? Scraping the poll pages every 10 minutes seems like it would cause a lot of unnecessary requests to HN.
Also, you probably consider any poll that's not on the first few pages of the 'news' or 'newest' sections to be complete. Sure, they might change, but they're not going to change by enough to affect your graphs.
The only way to 'listen' to page changes is to scrape it unless the web-page provides a notification service. Since that is not the case with HN, I had to resort to scrapes.
great job, Shishir. are the legend/poll options in the same order as shown on the original poll? i ask because the colors are a wee bit difficult to differentiate. feature request: link to the original page.
