When a deal with a prospect Organisation is set to Won, the Org type should automatically change to Customer. Which should then push out to all the contacts within that company. i.e. they should all now be labeled as 'Customer'. 

In light of the recent acquisition of Mailigen for email marketing by Pipedrive, it is important that segmenting audiences is possible in this way.

If Pipedrive want companies to use Mailigen for their email marketing, the CRM system needs to be able to do this automatically.

Currently, AFAIK, this can only be done on a one-by-one basis or via bulk editing.