For IDE Connectors we need the following info exposed in a regular way (with a kosher REST API)

• all info a specific build (something like getBuild(project, plankey, buildnumber) ) and not only for the last build from given plan or last X builds (like it's now)
• "failing since..." information (or: getLastPassed)
• "fixed in" information (for an old failed build)
• getNewFailedTests
• info about current activities (i.e.. queued builds waiting for executing and build being executed)
• build logs of given build which is currently being build (the same functionality which ajaxy js in Bamboo web UI uses to show log of a build which is currently being built). Ideally obtained in a loseless way (i.e. if we periodically poll for current output we will have a guarantee to retrieve complete build log without any holes)

I am putting everything in one bucket. Feel free to split it into as many separate issues as you wish.
Let Edwin prioritise which is of the greatest importance.
For me: build logs of builds currently being built look the most interesting, as I would love to have in IDE the following functionality:
Execute given build and then immediately see in the console its progress and output (clickable of course)