Is there anything that is going to be done post-merge to handle links in questions and comments to other questions? For example, I have a comment here: Sharing buttons statistics. It points to an old UXExchange question. That question was moved over - Are 'share this' buttons really effective? , but my comment is now pointing to Best ways to replace the combobox selection (aka single select) for touch interfaces.
Unless someone from the team says otherwise I think the only thing that can be done is for those of us that find these broken links to fix them manually. However, that only works for links in questions or answers.
If you find one in a comment then flag that post for moderator attention so that they can edit the link in the comment.
Given that the dodgy links will be "uxexchange.com" they would be discoverable in the database - but they'd have to be removed as we can't expect the team to go hunting for the post, especially given that the post might not have been migrated.