Dunno the finer points of terminology, but this essentially developer-unlocks your phone, i.e. it uses the same mechanism that's used to let you sideload your o

Dunno the finer points of terminology, but this essentially developer-unlocks your phone, i.e. it uses the same mechanism that's used to let you sideload your own apps for testing if you're officially registered as a developer. The difference being that it's cheaper (and possibly less of a hassle to get?) and doesn't actually let you put apps on the app store. I think that's different from the iPhone jailbreaks which don't play as nicely with the security mechanisms, but again I'm not really up on the details there.