A few of them exist in the real world - they gave out a thousand or so at PalmOS DevCon. To me that sounds like it shipped, even if in small quantity. These were not hand-built 3d printed prototypes. These were real devices with real injection molded silver plastic cases, operational slider mechanisms, working cell modems, and all.
I think "shipped" usually implies that one could buy them in some sort of official way. So for example the original chromebook CR-48 wasn't really "shipped" in that sense since you only got them as a devkit in conferences and similar, but the Oculus DK-1 "shipped" since even though it was a devkit you could buy it from Oculus.
At least that is the way I've seen the term used when it comes to development hardware.
