In the US, major carriers Verizon and Sprint have operated CDMA-based networks whose devices did not use SIM cards. I think it was the iPhone 4 that Apple once shipped 3 different versions of in the US: AT&T (GSM), Verizon (one set of CDMA bands), and Sprint (another set of CDMA bands).
But did you notice that Sprint is supported in this announcement? It is because LTE does in fact use a SIM, even on the carriers that rely on CDMA for voice. Fortunately for the iPad, it has no voice requirement.
In reality, there is the technical means to support this on ANY carrier. You just set the IMSI or ESN in software on the microprocessor and then hit an API at the carrier telling them to pair X device with Y unique ID. The difference now is that no one before Apple has had the weight to get the carriers to go along with this, since it encourages modularity and discourages device and carrier lock in.
In US you just get a phone with everything pre installed and sim tool :). So this thing does make it easier for Apple and a bit more convenient for users
what did you do prior to the advent of 10-band GSM radios?
I'm in the US and I've almost always bought cheap unlocked phones and SIM cards, but until recently I've had to hunt around to get the right variant of a phone for my preferred provider. Eg. T-Mobile uses 1700/1900/2100Mhz, AT&T uses 700/850/1700/2300.
The latest iPhones and some other phones now have radios that cover all frequencies, but those radios are expensive and typically only come on phones that cost more than $700.
Here, you got a separate SIM even with Apple phones. It's just how it's done.
The only toy I remember not having a separate SIM card was Amazon Kindle (the e-ink reader), and that's because they try to hide that the SIM is even there (and it's kind of weird).
Sure, there was no other choice. I'm just saying that if anybody was going to introduce a universal SIM in the USA, I would expect it to be Apple, and for exactly the reasons I described :)
For all 3 major carriers, you just get your phone and in a separate envelope, you get your SIM card.