You've heard about the one-touch jailbreak exploit. You think it's something you might want to try, but then you worry: what about iBricks? Will the jailbreak unlock my phone? Fear not. Jailbreaking reassigns the root of the iPhone's file tree. It in no way affects your iPhone's telephony functions or baseband/modem areas. Once jailbroken, you can run any of the unlocking applications but jailbreaking itself has nothing to do with unlocking. If you want to un-jailbreak, just restore your phone. It will not affect your upgrade path the way the older unlocks did.
And what about iPod touches? Will the next firmware upgrade turn it into a brick? Almost certainly not. And if you're worried, just restore your touch to a pristine state before you upgrade.
Thanks to everyone who wrote in to ask.