It seems strange to me that they are bragging about syncing between mobile and the web, but the only web SDK they provide is for JavaScript - I can't even find REST documentation for the Datastore API.
I love the idea of cloud apps that use user-provided datastores. It makes it both cheaper for a startup (because they can crowdsource their data storage) and easier for users to control what data services have about them. Google Drive already provides a service whereby I can store a user's data in his Drive account without cluttering his filesystem with my app's metadata. Dropbox Datastores sounds like a similar feature, but it's way less appealing to me if I can't talk to it from my backend.
I love the idea of cloud apps that use user-provided datastores. It makes it both cheaper for a startup (because they can crowdsource their data storage) and easier for users to control what data services have about them. Google Drive already provides a service whereby I can store a user's data in his Drive account without cluttering his filesystem with my app's metadata. Dropbox Datastores sounds like a similar feature, but it's way less appealing to me if I can't talk to it from my backend.