I am afraid there is no firm roadmap published but we are working on the main features of the control. For the Q3 2013 we are planning to add databinding, a LiveTile and to expose the tiles as separate controls. We can also add events for the drag and drop feature, but I cannot guarantee they will be both server and client-side.
You can monitor the release notes to see what becomes available when Q3 2013 is out.
If you want a feature you do not see in the control you can search in our Feedback Portal
to see if it is already requests in order to vote for it, if so. If you are the first - submitting a new one with a detailed description of the feature behavior, how it should be controlled and its use case will help us evaluate it.
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