I took a look into Hacker News hotness algorithm a month or two ago, and it is way more complicated than just points and time. Youtube videos probably don't rank that high compared to other websites. People could be colluding, but I think it is more likely there is more to ranking than we can understand from what we see.
[Edit: This was in response to someone asking why it wasn't on the front page.]
It got 20 to 30 votes in the first hour but was buried at around 50. Whatever algorithm they use, I'm not impressed. Maybe Arc just can't handle complex expressions. :-)
