[csdigi]

Backbone like spine has moved to support the "asynchronous UI" in its models by default. The general philosophy is that all storage should seem local, and the interface should wait as little as possible with data being synced in the background (given the appearance of success to the user). However this is not always possible, and needs to be worked around, as some people have covered (validation for uniqueness in a DB). But it was generally accepted as a sensible default stance. To read about it from the Spine author checkout his blog and presentation.

http://alexmaccaw.com/posts/async_ui http://www.infoq.com/presentations/Asynchronous-UI