From the commands currently supported, it looks like it's an update tool to update the core and to update plugins.
Here are some commands I think may be helpful and a few notes:
* upgrading the core could check the installed pup and mysql versions for changing WordPress dependencies. i.e.: latest wp versions had php requirements changes. You wouldn't want to be able to update unless your system is up to date * secure: command to secure the wordpress installation based on best practices * language: download/install language packs * backup: tool to backup wp-content and the database (optionally to another server) * restore: restore from a backup * migrate: copy to another database, optionally change DB/WP prefix, migrate/merge user IDs, etc. Could be complex, but the use case would be to help moving to a multi-site single DB installation.
I'll probably thing of other stuff.
I like that plugins can be developed for this tool.