UPDATE: Ars Technica reports the same as what we heard. Sprint confirmed that it will require an international roaming plan in order to use the micro-SIM for GSM roaming abroad. You won't be able to use an international micro-SIM card in your Sprint iPhone 4S. We knew it was too good to be true.
Looking to do a little traveling abroad, but don't want to pony up for crazy expensive roaming fees with that new iPhone 4S? Well, if you're getting an iPhone 4S on Sprint or Verizon, you'll end up saving a lot of money because those carriers have unlocked iPhone 4S devices or will unlock them for you. AT&T won't.
Macworld's Jason Snell reports that the Sprint version of the iPhone 4S will ship with its micro-SIM slot unlocked and Verizon will unlock any iPhone 4S micro-SIM slot after 60 days (if you have a good record). What this means is you'll be able to buy a cheap micro-SIM card when abroad, stick it into either of those iPhone 4S and you won't be charged roaming fees.
It's unclear whether or not there are any other securities that Verizon and Sprint have implemented to circumvent using a local micro-SIM card from AT&T or T-Mobile once the iPhone 4S is unlocked. If the micro-SIM slot is unlocked to take any international micro-SIM card, we don't see how a local micro-SIM card from a GSM carrier wouldn't be accepted, unless of course, there is some kind of software lock on U.S. GSM carriers.
Don't travel? Then this is all useless to you. The AT&T iPhone 4S is probably the best one for you then — it's the fastest one in the U.S. Apple's also selling an official GSM-unlocked iPhone 4S next month.
Snell says the statements are directly from Apple and that he believes using the unlocked micro-SIM slot is only for international roaming, meaning it won't work with any U.S. micro-SIM cards.
Until the iPhone 4S is officially released this Friday and customers jet out to test it, we won't be sure what's what. We called Sprint ourselves and were told the micro-SIM slot is not unlocked for international use. However, as the info is relatively new, it's possible the info hasn't trickled down to Sprint employees or managers yet.