This page is mostly forward looking. While Arbital does already have a basic comment system, all the other features are not yet implemented.
In a debate about a complex topic, there are multiple ways to get lost. One wrong step in the reasoning process often leads to an incorrect conclusion and disagreement. The process of discussion is most useful to find these disagreements and resolve them. Reading a discussion is most useful when the reader has a similar disagreement, and reading about how the disagreement was resolved (or at least the current best arguments) will help them change their mind. One way Arbital will have more useful discussions is by having better tools to help the reader find the parts of the discussion that will be most helpful to them.
These kinds of debates are all over the internet, and vast majority of them are not unique, i.e. there is a very similar argument elsewhere. This can be prevented if Arbital can guide each reader to the one place where the particular discussion they want to have is happening (or, most likely, already happened). We dream of a world where everyone only needs to argue once about whether Vitamin D3 is a better nutritional supplement than Vitamin D2, and every time anyone on Earth raises a question that's already been answered, they can easily find the answer and reasoning on Arbital.
No longer will people be able to claim to know things about unsettled topics. Just like Wikipedia settled arguments about facts, Arbital will settle unresolved questions.
The quality of the community and the content are the most important things on Arbital. While most online communities usually start with high standards, it seems that inevitably many of them go downhill. Arbital's answer to that will be karma and dominion. Those have proven themselves to work reasonably well on StackExchange sites. However, SE only gives the user three choices when it comes to evaluating the quality of an answer: upvote, downvote, or do nothing. Furthermore, most votes are dispensed by the people with the lowest standards for upvoting, and every user's vote counts as the same. We have concrete plans to resolve both of those problems, which will help Arbital's expert users have more control and influence in their domain of expertise and will result in the best content being more visible.