New feature. By silencing any dissenting opinion, it effectively creates a "discussion" where only those who agree can participate.

That seems unfair to the discussion, doesn't it?

Much like others here, I came to hubski via reddit.

Methinks that I'll still browse reddit, but I see no reason why hubski won't appeal to many redditors, should it become widespread. In fact, I anticipate waves of meta-redditors coming here on the premise of joining the next big thing.