From the publisher's website:
Adventurer is, as the name suggests, a solo role playing game.
In developing the game, the aim was to bring a fully-fledged role playing rules system to the gamebook or interactive fiction style adventures that have been published since the 1980s. These adventures have often had simplistic rules by necessity, but we wanted to try to bring you something different, something for the hardcore gamer to sink their teeth into.
The game itself is due for general release in early 2013. However, we have decided to allow you to see the rules manuscript right now! This may still be subject to some tweaks, though we do not anticpate major changes at this time.