Interesting and good point John.
While "Digital" is a misnomer for most, "Class-D" or "Switching output stage" in general are not accurate terminology for them as well in general. One thing that they all do have in common is the use of PWM in their circuit. The use of PWM is something you won't find in the "analog" classes of amplifier.
PWM and Class-D amps also goes hand-in-hand by description (see Wikipedia). Often they are refered to as one. In reality, it is true that Class-D is a PWM amp but not necessarily true the other way around.
Maybe "Analog" too is a misnomer as "some" of these amp brand theirs as such. It seems that this is due to the fact that in the current amp world such terms or branding as Digital, Class-D, PWM is somewhat of a turn-off. Wether it is misinformation or lack thereof, maybe it is bad publicity or lack of exposure we just don't know. Confusion has run-amock in the CE world.
What shall we call these "Digi-Amps" (as I have labeled them)? I think that question is best answered by the proper authorities. For the meantime, I will refer to them as Digital or Digi-Amps.
PS: Your welcome to coin a cool name for it that I may be inclined to use.