What about atv? Stuck on 5.3 (iOS 6) for a year now or so. Atv3 still hasn't been hacked strangely.
That is strange.
I bet once/if they open it up to third party apps, an atv3 (or 4?) jailbreak would become a lot more likely, since Apple would have to open up the device a bit (after all, this particular jailbreak was due to loading an enterprise certificate, of which there's no way or need to do currently on an Apple TV).