Can a Contact be part of Partner Portal as well as Customer Portal in salesforce.com?

Answer: Customer Portal and Partner portal depend on the user object and are not related to the contact object. So to enable both portals for a Contact we need to create two users which will utilize two different salesforce.com licenses, one license for Customer portal and other for Partner portal. Yes, a contact can be part of a Partner Portal as well as Customer portal in salesforce.com. Both users created for a same contact will have two different profiles, One for Customer portal and other for Partner Portal.