Tasks, issues and requests that have been accepted, assigned, and otherwise queued for work.

Conceptual agreement that a patch on the issue would be accepted (if of sufficient quality)

Tasks, issues and requests that are actively being worked on.

Issue currently pending confirmation that a patch for it would be acceptable

(Significance) Affects compatibility with some environment/configuration/version

Issue has had first level triage

The submitter is working toward change (providing capacity) but wants to get feedback/support