It's actually pretty incredible; I was expecting to see simple "dumps" of CC info and bank login credentials, but it was much more sophisticated. Sellers were offering "packages" that would include bank login information (priced according to account balance), lists of IP addresses that were known to be flagged, SSNs and address information to help with security questions, and guides for how to best use this information.
Definitely seems like it'd be easy for a criminal with a little tech know-how to make a full time job of buying and exploiting this info. Based on the prices I saw, it would only take one successful fraudulent transaction out of many attempts for it to be profitable.