I'm having the same issue, I hope they're doing something about it. I mean how hard can it be to keep the servers up, they do it 24/7 just a factor of laziness and it hasn't changed all day. Activision and whatever left of their skeleton crew need to pick up their act. I bet people are just about ready to start a class-action lawsuit just to prove a point that their unbelievable lack of customer support and the way they just sell their incredibly undeveloped broken games to the public isn't tolerated by federal law all marketed products should be sold as advertised.

Activision not very active I would say

Hello!

It looks like several PS3 users are encountering this issue. We're looking into the cause as I type this.
For now, can you:
Try signing on with another PSN ID
Try plugging your ethernet cord directly into your console if you're on wireless
It sounds like you've already tried power cycling your modem and router, but if you haven't please do so

Finally, try contacting your ISP, they may be able to give you information regarding any outages.

I apologize that we don't have a concrete solution available for you guys just yet, but we'll update you once we do.
^LM

Have even tried getting friend invites to join a game and can't get in that way either.

Australia, ISP Telstra cable internet.