A lot more has changed over the last year than the technical details of the Steem protocol. The entire blockchain sector has undergone a seismic shift and the Bluepaper is our response to that shift. People of all walks of life now turn to these documents to learn about our technologies. This is especially the case for Steem which is an open and decentralized database designed to power applications which serve the needs of ordinary people; not just those who already know and love cryptocurrencies and blockchains.
More info: https://steemit.com/steem/@steemitblog/announcing-the-steem-bluepaper