Hacker News doesn't really rub karma in your face like the article describes Plurk as doing (headless dog?!).
Of course, you can choose to think that the karma number in the corner is actively mocking you, just as you can choose to click on other people's names to compare yourself to them. How much these site features bother a person says more about the person than the features, I think.
Yeah, here on HN nobody knows you're a headless dog. You have to deliberately click on someone's name to even know their karma score... and there isn't much reason to care.
(That's just some random user's page, as linked from the front page.)
I can see how that would be enough to put me off a site for life.
And is it just me or is the "giant, echoingly empty, horizontally scrolling timeline" layout the stupidest design decision since... well, the name "Plurk", which sounds like something your dog might say if he were missing his head?
