How about a SIP?  "Useful result values."  Or a SIP annotation.  But seriously, it would be nice if github's issue tracker could be used that way.  (I don't know, maybe it can, especially if a label can distinguish backlog items from PRs.)  I do like the idea of an issue tracker that manages backlogged TODOs effectively, i.e., not visible all the time but not forgotten either.  Workflow would be like a line note.  The tracker could "show TODOs" for a file, or checkout a file with TODO comments inserted (it's a kind of versioning problem, so maybe there's a todo branch; maybe it warns you if you commit a change without resolving a conflicting TODO, with of course a simple dismiss button).