While doing some security blog reading I came across three posts which were dealing with underground hacking groups:

• The Invasion of the Chinese Cyberspies (And the Man Who Tried to Stop Them)
• Myfip Intellectual Property Theft Worm Analysis
• So who is Diabl0?

The first one is a much bigger story and doing the rounds on security blogs as 'Titan Rain', it hints at a very large powerful hacking underground, being a newbie to the security world I sometimes forget people like that exist and end up focusing on automated worm attacks and script kiDDiEs.

The third has an interesting update on the arrest of the author of Zotob and Mytob, including the group he belonged to, 0x90-Team, getting hacked and told to stop training script KiDDiEs without adding any actual knowledge. While the second has a great analysis of an interesting worm written for 'commercial' purposes.

So they all point to a criminal underground I don't see much each for a different purpose. A loner looking for intellectual property, a group of script KiDDiEs trying to break things and an elite hacking group.