Origins of Malu is most likely on your short list for games to watch. The developers are promising that the game will allow players to experience a true sandbox environment, and from their early discussion of the game, it's certainly promising thus far. Of course, the real verdict is going to come when the game goes live, but until then, the team at Burning Dog Media is planning more updates to keep players hooked.
An earlier posting on the official Facebook page claims that there are two major announcements about the game coming this month as well as information about how PvP will work and exactly what the team is doing for it. There's also the promise of official forums on the site and developer videos, both chances for future players to get engaged in the development and refinement process. If you're following the sandbox field, this may be worth keeping an eye on.
[Thanks to Halldorr for the tip!]