We now have a dashboard up on Swift.org to track remaining tasks for ABI stability:
The contents of the dashboard (which we may refine over time*) are largely drawn from JIRA and the ABI manifesto:
The tasks currently tracked on the dashboard are fairly low-level details concerning the ABI itself. These include details that should be re-reviewed and finalized, or finishing up areas we know are incomplete.
* - One area that is currently under represented in the dashboard is the work on the standard library. The work needed to be done is fairly well understood; there's just some effort needed to aggregate that information into rows in the dashboard.