Apple has issued a notice that unlocked iPhones could suffer permanent damage when they update the firmware, and reminded customers that such damage is not covered by the warranty.
The process of unlocking an iPhone is complicated, and involves code running at a pretty low level in the OS. Users may feel confident that they can always re-flash their iPhones using iTunes, but even that requires a working kernel (minimal OS) on the phone - damage that and you've got a Jesus doorstop.
Such damage is unlikely. Far more probable is that every time an update is installed users of unlocked iPhones will have to unlock them again, but Apple felt the need to remind people of the risk they take when unlocking the handset or installing third-party applications.
Engineers inside O2, the UK operator deploying the iPhone in November, are under the impression that Apple will be able to re-lock phones to their network when they're updated, but that will depend on the unlock process used and if Apple can be bothered to apply the resources needed to reverse it.
The assumption among many iPhone buyers seems to be that no matter what Apple does, the hackers will make everything work. The faith in techno-anarchism is touching, but may be misplaced if Apple just reverses everything with each update.
One Apple fan has even suggested all this is a good thing as it will drive Apple to create must-have upgrades, to encourage users to install them, making the iPhone an even better product for everyone. ®