Chris Hagedorn, PSN Loyalty Programs Manager, writes on the Playstation.Blog :
"We wanted to share with you the new ability to add more convenience to your PLAYSTATION Network experience by linking your PlayStation Underground ID with your PLAYSTATION Network ID.
The PlayStation Underground is the community of PlayStation fans you join by creating an account on PlayStation.com or by registering a PlayStation product. As an Underground member, you can participate in community forums and manage your account on PlayStation.com. Underground members are also kept "in the know" about new games, hardware, events and contests-so you can maximize your PlayStation experience."
More after the jump!