By integration I meant the very basic scenerio:
a) Your affiliates send visitors to your site.
b) Visitor becomes a premium member
c) A commission is awarded to the referring affiliate.
In short you can achieve what you are after too. There is a function that can be used to create an affiliate account. So when a member register you just have to pass in the details to this function to create an affiliate account with the same details. At the moment this work is done by manual tweak but I am in the process of making it so you can enable this option from the settings menu of the plugin.