Definitely good to read a fair review of what this site is all about. I have been recommending it to a lot of friend even those who weren't into Reddit. Sometimes you felt a little weird recommending Reddit because of its toxicity, but Hubski is a very easy recommendation for anyone looking for interesting reads, and discussions.
On the other hand it seems like the author gave a very superficial look at the other alternatives. For instance, nothing about Snapzu's gamification or tribe system was mentioned in the article. And he's painted the others in quite a negative light.Definitely good to read a fair review of what this site is all about.
If I had to guess why I would maybe say that Hubski is really quick to teach you about its mechanics. I knew what I was doing after 10 minutes of actually being a part of the site. The other sites or at least the ones I tried weren't as quick to educate the user. Granted it doesn't take away from the fact the writer did a poor job reviewing the other sites, it just also means he/she may havr done a shallow job.