There was a question on French Language & Usage which belongs on meta, so I (a ♦) migrated it there. This generated a community flag telling me to add a comment. I don't think this is necessary: a migration to meta is transparent enough that it won't confuse the user that much (and I did leave a comment anyway, but on meta, post-migration).
Also, I received a notification about the new meta question. Hey, I knew about that one already. I admit this is an edge case, but when a moderator migrates a question to meta, it would make sense not to push that question to that moderator's inbox, like when that moderator is the author of the question.