We are evaluating if we want to migrate from a web-based forum to using the Desk/Community forums for our customers.  We have ~3,000 customers that ask each other questions across a number of topics.

But as they are our customers, we won't be making the forums accessible to non-customers.  Is there a way to assign groups to contacts based on a field or value within the CRM?

Ideally, anyone we set as a customer in the CRM would be automatically within the customer user group within the forums.