Criminals use Wi-Fi to hide their tracks: But not very always successfully. Some criminals aren't very bright and are using networks adjacent to where they live and having stolen goods shipped to them despite using other people's networks. Others are more clever and their use of random Wi-Fi networks prevents them being tracked down by law enforcement as they engage in death threats, fraud, and cracking.
The article also lumps together unsecured business and home networks with free Wi-Fi networks: "Ms. Hubert [the supervisory special agent in charge of the Cyber Task Force at the F.B.I. field office in Buffalo] says one group of hackers she has been tracking has regularly frequented a local chain of Wi-Fi-equipped tea and coffee shops to help cover its tracks."
I welcome this article because there has been a lot of speculative coverage before this as to whether Wi-Fi was being used in this manner. Now we have a number of agencies citing actual cases in progress or already in court.
The SBC number is a little odd, by the way: the spokesperson says that SBC has shipped one million Wi-Fi routers to its customers with encryption turned on. But I saw a number months ago that said that SBC had shipped nearly three million routers to customers (out of a population of five million DSL users at that time). Did two of the three million get shipped with encryption off?