The Sycamore API will certainly evolve over time. As we get feedback from developers who use it and customers who want to consume it we'll make changes and tweak it. We will aim to never break the API and always keep it backwards compatible. We will, however, make additions to the API which will not affect applications already written. The version will only be incremented when 'breaking' changes need to be made that would interrupt backwards compatibility.
API Version: v1 Release Date: Summer 2014