The article above summarizes the current situation with CableCard — it's just barely starting to become availble.
Some background on CableCard …
CableCard is a small standardized electronic card that you plug into a cable set-top box (or DVR) of your choice. The idea was that consumers would be able to buy their own set-top box or DVR (e.g. at BestBuy), and the cable company would send the consumer a CableCard which contains the security/access-control hardware to prevent cable theft.
CableCard is a hardware solution to the cable companies security/access-control concerns — you have to get a physical CableCard from your cable company. The article also mentions a software solution under development, known as Downloadable Conditional Access System (DCAS). As a software solution, you would not need to get a physical piece of hardware (like a CableCard) to plug into the cable box you just purchased from BestBuy. Rather, the cable company would electronically send "keys" to the software in your cable box.
After years of little activity on the CableCard front, much of the recent activity is due to a March 2005 FCC ruling (pdf) requiring cable companies to stop shipping "integrated" cable boxes (including DVRs) by July 2007 (in 2 months). To avoid fines, the only solution available to cable companies today is to ship boxes that support CableCard.