There has been discussion about a distributed blogging application for a few months now called "MyI2P". While the original discussions were lost, we were able to retrieve a Google cache of it. It isn't pretty, but it includes the basic overview and some discussion that ensued.

The application itself is not yet implemented, and the ideas behind it have been made less ambitious over time, but they are still valid and the current plan is to have the core MyI2P functionality available along side the I2P 1.0 release. That will include a distributed address book to enable secure, distributed, and human readable naming by sacrificing the need for global uniqueness - basically everyone has their own local address book and can 'subscribe' to other people's address books, letting MyI2P periodically retrieve new name to destination mappings (leaving conflicts up to the user to resolve). In addition to the address book, there will be a distributed blogging system using a reduced and secured subset of bbcode to essentially provide an anonymous LiveJournal with a 'friends list' and transparent access control (authenticated by the I2P datagrams with rules defined based on the address book).

Additional functionality, such as integration with a DHT backing store or swarming file transfers for 'attachments' can be added later. Email may or may not get in the first pass either, though its implementation is essentially just a blog entry with private access, so perhaps some UI designer can come up with something. Exporting the data to RSS or access through ATOM will be an option down the road as well.