A distributed information publishing platform. It could be used as the infrastructure for academic publication, blogs or social network etc. There are a few reasons to make such a platform decentralized.
First of all, public information and the right to publish information should belong to the public. The content published by the user should not be controlled by one company. When the author made the content public then every one should be able to access them without paying a third party to get the permission. As a byproduct it will also encourage innovation.
Second, it is more difficult to lose important information or access to information due to server breaking down as the information is likely to have multiple copies arround the world served simutaneously.
Third, there are many other advantage with proper p2p implementation. For exmaple, on bitpub the information is retrived by its ID (hash of the information) and not by URL, so it does not have the common problem that URLs often change and fail to work after some time. Another example is through many types of relation between pieces of information published like "comment", "reference" etc, it forms a netwrok of hash chain which can be used as a standard trusted timestamping.
Pleas see the project wiki for more information.