Wow.. that sounds like a good name for a movie "Coming to the big screen in 2008 - Stealth Hackers!"
This isn't really a new thing. Hackers as we know them (and I use the word hacker in the evyl-skript-kiddie-with-toyz way and not the kind-open-source-guru way) are slowly moving toward the idea that "cool, we can make good money from this!"
In the past hacking was really done for the cool stories hackers could tell their friends to get street cred. Events were big and done for the headlines. Hacking was like graffiti - it was out in the open and done so people could see. Hackers didn't want to get caught but they did want their work to get noticed.
I believe that these people are still out there and still trying to do big things. I think that their work is also being converted over to the new types of hackers.
The stealth hackers are not necessarily very computer literate. They take the research and exploits of the big-bang hackers and craft it into tools like malware, root kits etc. They don't want to get caught, obviously, but they don't want to be noticed either. These are the botmasters who want to use the world' s computers to gather information that they shouldn't have. They also want to use computers to send spam and the longer they can stay undetected, the more money they can get.
There are different levels of technical ability in the realm of the stealth hackers from those that write exploits to those that deploy bots to those that sell information and those that just buy credit card numbers.
I believe that both groups - traditional hackers and stealth hackers will grow in numbers but that stealth hackers will grow much quicker.