We've just received word from the iPhoneSIMFree team: they claim that their iPhone SIM unlock solution (which we documented on video here) doesn't send your iPhone with 1.1.1 Firmware into Activation Limbo, unlike anySim. We still have to test this, however. Read what they say after the jump.
We have successfully completed a test of the 1.1.1 firmware update on IPSF unlocked phones. We are very pleased to report that the phones are still fully unlocked, and if you are using an original activated AT&T sim, you can activate and use the phone with no issues at all. Unfortunately, currently there is no way to jailbreak/reactivate the phone for use with a sim card other than the original AT&T card. Therefore for our customers who have no immediate need to use alternate providers and are still using their AT&T card, you are welcome to update your phone. For the rest please be patient, as the jailbreak issue is something that affects much more than just the unlocking. The thousands of open source developers who have put a cumulative 10s of thousands of man hours into various apps and tools now have no way to get them onto the phone as well. We are all looking into the jailbreak issue as it affects us all, and we will keep updating our site as well as the open source community at large with any information we can about this.
We also tested an AnySim unlocked phone, and after the update it appeared to be relocked. The IMEI was reported as 004999010640000 (see below), and a T-Mobile sim was reported by the phone as an "Incorrect SIM" rather than the new "Different SIM Detected" message.
However, our recommendation still remains the same. Even if you could keep using your unlocked iPhone after updating, you can only use it with AT&T, which defeats the point of having an unlocked iPhone in the first place. Just don't upgrade. [iPhoneSIMFREE]