The Feb 17, 2009 FCC mandate applies solely to full power over the air TV stations (OTA). Has nothing to do directly with Cable.
That being said MSO's are working transition to full digital, or at least expand digital offering for the same reason it makes sense to do Digital OTA - it frees up spectrum.
That is correct; it only applies to OTA TV. The people writing these stories (and evidently Verizon's PR department) repeatedly get it wrong and I suspect that is on purpose. Verizon transitioning to digital only has nothing to with the OTA deadline.
Of course, someone could email Eric Rabe and set him straight...