The update is not bricking phones. It is absolutely illegal for a company to release software to permanently (and obviously maliciously) damage software installed on your product and or the product itself. Apple have not been very careful with what they've been saying about this and seem to have been put into serious legal jeopardy early on. This is why you've seen numerous statements coming from them to clarify the issue.

Their position is that some 3rd party software, namely the unlockers, are what is damaging the iPhone. Their updates might not install properly with this damage done and may leave you with an inoperable phone. This damage is not covered under warranty.

If it is ever discovered that their updates contained active code to maliciously affect your product, they could be in a world of hurt, so they have to be very careful here. It's really no different than many other software releases where no implied warranty is provided and you install at your own risk. Installation may have bugs and may cause incompatibilities, but these must be the product of pure chance, otherwise you're looking at the equivalent of someone distributing a damaging virus/trojan.

I suspect all will be hacked open again, but I wouldn't want to make bets on a date. Could be later today, in a few days or in a few weeks.

Most people with an unlocked phone know better than to apply this update and will stick with 1.0.2 until a solution is found. I'm also very curious to see what happens in countries where anti-locking legislation exists.