Well, not really. Cable does not use ATSC to transmit digital. They've been using QAM for many many years, and will not be changing that.If your set is less than 3 or so years old (probably is), it has an ASTC (digital) tuner and you won't need a converter box unless you want to receive premium channels from your provider.
As I indicated above, CapeCodTenor's issue isn't related to the over-the-air digital transition that is the context of this thread, at all. Rather, it is almost surely just related to that specific cable head-end and its decision to start offering more advanced services. Contrast that with TwinsinCA's scenario which is very likely to be related to the over-the-air digital transition.
Yes, rent it, actually. And very few televisions were ever produced with CableCARD slots, and practically none are currently being produced. Customers just didn't value them highly enough to warrant manufacturers producing such televisions in large quantities.Even with that, some TVs have a "cable card" slot that allows the TV to receive those premium channels without a service provide box but (I believe) you have to get the card from your provider.