As a translation coordinator, I want to see in a single page all the content that needs to published somewhere and is ready for publishing, so that I can publish it.
This means showing all message groups in all languages, filtered by status (ready).
The system would replace categories such as https://meta.wikimedia.org/wiki/Category:Translations_by_status (old standard translation request) and https://meta.wikimedia.org/wiki/Category:Translation/Fundraising_2011/Jimmy_Letter_002 (https://meta.wikimedia.org/wiki/Fundraising_2011/Translation/Project_report#Language-focused_request_template ).
See also https://meta.wikimedia.org/wiki/Help:CentralNotice/Translations for one current usage of workflow states on Meta-Wiki.
Related to bug T36299: Automatic workflows (a fully automated workflow would include the publishing part).