It's a bit like flashing your ecu. Not illegal but no warranty either. It seems there is still no genuine jailbreak for the gen 3 Apple TV. I think you are right about some being better than others. From what I understand an untethered jailbreak is better than a tethered one
That's right, unteathered means that if you hard boot it (power it off) you loose the jailbreak so it must always be powered up. Shame on the atv3 not being hacked....I liked the jailbreak on the 2 (ive done a couple) but then having said that essentially the jailbreak lets you run xbmc and you can run that on almost anything these days.