I've just seen that the Create/Update Opportunity action is being phased out and it will soon be unavailable in new workflows.
As this action is VITAL for my workflows, I've tried the new "Create Opportunity" action but I've realized that it doesn't accept dynamic dates for my custom fields. This is TRAGIC for me and it would be a BIG DAMAGE for my business (and for many other people using this kind of action)!
I need to keep on creating a dynamic "Expiration date" for each opportunity, referring to dynamically calculated date using the "Date Manipulation" action.
I really really hope that somebody will fix this before the existing "Create/Update Opportunity" action will be removed!