Forum features could be added to BTS as soon as the key graph is in place. Assuming people are willing to pay their $0.02 to post
Have it like reddit where you up vote with your stake. That way consensus/majority on any issues can be found rapidly. Will increase our ability to respond and adapt to any threat or opportunity.
We could (and should) go far beyond simple reddit up/down votes. We should optionally use Key Graph to publicly delegate our trust (and stake) to accounts/identities we trust, in addition to having our own private weights for each account we trust. This can also be done on a topic by topic basis. Then we can appropriately weigh the approval/disapproval of a post by accounts based on this web of trust and reputation and on the topic the post belongs under. Thus I could order/filter the posts by one of many consensus measures (meaning I get the same ordering as anyone else choosing the same consensus measure) and I could also order/filter the posts by one of my private subjective measures.
There are so many possibilities in this space. I have many more ideas that need to be better developed regarding a Social Networking/Forum/Discussion DAC. I think all posts should link to recent previous ones within the relevant branch of the discussion thread forming a DAG (directed acyclic graph). Then, periodically anyone can post a hash of a recent post to the blockchain to protect any of the posts referred to in the chain from being censored. I don't think there is any need to bloat the blockchain with hash of
every single post. If a "trusted" third-party does this on a frequent basis, we can get a decent upper bound on the time a post was made. A better lower bound can be done by the poster by including a hash of the most recent block in the meta-data of their post. Even if the timing isn't precise, the DAG will ensure that the order of posts was at least not altered.
Payment for the posts would need to be figured out. I don't like the idea of paying for each post (again blockchain bloat). I think the entities providing the frequent timestamping of posts can also be the entities hosting the actual encrypted contents of the posts as well as managing the metadata relationships between the posts. These entities can then be paid by the posters through micropayment channels instead.
Other things to figure out include managing group ACLs so that only participants in the group have access to the private key used to encrypt the contents of the post. Migrating groups over to a new one anytime an addition/deletion of a member of the group is necessary (and notify members of the new group of the change and the new private key to use to encrypt further posts). It should be possible to send notifications of posts to specific parties (by for example tagging them in the post) via something like the KeyMail system. Also, we would want to figure out the specifications for editing posts by attaching deltas to the original posts (to create a viewable edit history) and the specifications for adding metadata to a post like upvote/downvote/like/+1. Furthermore, it should be possible to create content-addressable links (with necessary decryption key included) within the post to encrypted content like images/audio/video held in a decentralized storage system similar to Maidsafe/storj.
I am very excited about the possibilities in this space.