It took the iPhone Dev-Team less than 24 hours to successfully perform a tethered jailbreak of the first iOS 5 beta, but hopes that an untethered jailbreak would be developed before iOS 5 goes public later this year have now been crushed.
R.I.P. – I just heard Apple killed the ndrv_setspec() integeroverflow and his friends in iOS 5.0b1 – if this is true the untether is dead.
The first successful iOS 5 jailbreak used the Limera1n bootrom exploit, which cannot be patched with a software update. Meaning, until Apple updates the current hardware, a tethered jailbreak should always be feasible.
As for an untethered jailbreak, however, whether it’s possible for hackers to develop a new exploit remains to be seen. iOS 5 could be the end of untethered jailbreaking.
The idea of having a device that could crash while I’m out and about and cannot be booted up again until I reach a computer is, for me, enough to drop jailbreaking. Would this be enough to put you off?