I normally would never link to a website called Malware Database, and if you're running a vulnerable system, you might want to be careful here.

BUT! Malware Database is mirroring Anonymous' Operation Payback blog (the original is down due to counter-counter-counter DDoS'in'), and it's pretty fascinating.

Update — 12/8/2010 — 8:24 AM
Mastercard.com is still selected as the main target and has not came back online since our last report. 7 hours of downtime and counting.

The amount of participants in the attackers chat room have soared to over 2200 people and there are currently over 1,700 computers in the voluntary botnet.

Update — 12/8/2010 — 12:26 PM
Mastercard.com still under attack with 11 hours of downtime and counting, but the target will change to Visa.com at 1 PM PST.

This is the first time that the group officially targets Visa.com, but we have already observed 106 service interruptions and over 12 hours of downtime for Visa since we started monitoring yesterday at 9PM.

I'm not a big fan of DDoS attacks generally. From experience: they suck. But the counter-attack against those who are attacking WikiLeaks is following the same principle that the U.S. and other governments have been using. The governments didn't like what WikiLeaks was doing, so they used political pressure and threats to corporations doing business with them to try to take the site down. Keep in mind that WikiLeaks has not been charged with any crime. Anonymous (and others) didn't like what those governments were doing, so they're using the tools at their disposal to counter-attack.