As the title says I'm curious to know what the user rankings are for, I just registered and I'm getting to know the site and its features.

Currently the ranking shows the order of the users according to the points (Bricks) they have in their account, that they have earned through the likes/upvotes on their posts. However, we have big plans for this system in the future, not only to make it more engaging and interesting, but also to make it possible for users to somehow use these points to get some benefits and rewards, so stay tuned!