As an enterprise agile user, I would like to be able to do developer capacity planning on Scrum boards

As a large enterprise user, we require the ability for our developers to provide their capacity (in hours) for each sprint so that the Scrum Master can easily create a sprint and assign stories without needing to confirm with each dev on each issue if they will have time for it.

Overall, JIRA Agile (formerly GreenHopper) is better and more efficient than previously used agile tools such as Rally, save for this one lacking feature.