Well... too bad for the suckers who subscribe to OnStar, I guess. I actually wonder how many of those 4 million are regular subscribers and how many are car buyers going through their free year of OnStar with purchase.
Really, I've never understood the appeal of OnStar (at least enough to justify the charge). Sure the Emergency Service thing is nice, but I certainly don't expect to be in an accident or deploy my airbags on a monthly basis. And even if that does happen, OnStar won't sell me as much as safety ratings on the car, so that I can get out safe and use my cell phone to call for help.
My mom had a year of OnStar with her Acura RL for free. The entire time, I'm almost positive she only used it once. At the dealer during purchase. When they introduced the OnStar system. "OnStar, How may I help you?" "This is just a dealer demonstration" "Understood."