reddit is useful in the way that it has so many varieties of subreddits with decent numbers of members. reddit has thousands of different communities, and it is the central hub for many of those communities. Everyone has their own likes and dislikes, and reddit can offer you a place to discuss them. You don't have to subscribe to those default subreddits if you don't want to. That's the beauty of reddit.

None but a few subreddits that I am subscribed to have pictures. And most of those pictures are educational. The subreddits I'm subscribed to are generally above average people, and they know how to make a great community. Some examples: /r/programming, /r/startrek, /r/books, and /r/netsec. Those are all great communities. People generally look at the defaults and think that all of reddit is like that. However, that is simply not the case.

I like Hubski; it's a great site. However, the only thing I see that Hubski could offer is an alternative to popular subreddits. That's not necessarily a bad thing, though. I joined Hubski for an alternative to subreddits like /r/AskReddit. (I'm so tired of all those pun threads.)