My colleagues and I started developing a document-store, which focuses on durability of the data taking advantage of new technologies like SSD, support for graph and geo algorithms needed in social networks, ease of use for the developer and minimal effort to operate for the administrator. The design goals are described here.
The ArangoDB consists of a server, a separate shell, which allows you to administrate the server, and a set of client API for various languages.
Though arangoDB is yet a young project, a couple of people started to add APIs for different programming languages/frameworks. See http://www.arangodb.org/api
Frank is twittering for the project on Twitter using @fceller. We've also a "generic" twitter account mainly for announcements called @arangodb
You can also subscribe to a low traffic announcement list on the connect page.