Don't the unlocking methods mostly finagle with the firmware? In theory, all you have to do is 1. don't update the iPhone software, and/or 2. restore the firmware to it normal state pre-update. A complete restore should take care of anything, unless the unlocking methods somehow prevent the software restore mechanism from recognizing or communicating with the iPhone. They're clearly not going to say what exactly goes kaboom, thus lending a hand to the folks unlocking things.
I'm curious to see what the folks who are doing the unlocking have to say, if they know how or where it would be fubared, or if they just call Apple "another Microsoft" and avoid the immediate question.
[added]OK, it seems that, according to folks who presumably know a tad more about this on Ars, unlocking the iPhone (*not* jailbreaking) requires "flashing the baseband (modem)" and modifying it. Thus, as it makes sense to me, Apple assumes that the lowest level firmware is intact with this coming update. If it's not, then it's ix-nay for the one-phay.
As for whether this is nefarious by Apple, I would find it slightly mean if they did this deliberately, but I'm neither surprised nor do I feel that this is "pulling a Microsoft" on users who signed on to unlocking their iPhones. Clearly, and by all common sense, folks who did this were fully aware that they were breaking their user agreements both with AT&T and Apple, and that they did it at their own risk. But if the firmware/flashing thing is true, the damage is only irreparable once you try to update, not before. Theoretically, you could restore the official firmware back to the baseband beforehand and all should sail smoothly. Of course, then you'd have to re-unlock it, making sure not to fubar the thing again...
Now, if we could do something about these companies having a stick up their butt about selling.accepting unlocked phones to their networks... but that's another matter.
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The good news: it looks like the iPhone 1.1 software update is coming on Friday.
