Apparently the 3g iPad is supposed to allow one to activate it on a month to month basis without visiting AT&T. Steve Jobs said you can activate the service from the device. So this must mean that the iPad has a 3g micro-sim already installed.
From this it should be easy to use it as a stencil and cut it with a #11 exacto blade. The problem is getting it back into the iPhone. It shouldn't be too hard to make an adapter out of cardboard (or the existing cut-away plastic. But I'm wondering how long it will be until some Chinese manufacturers start making iPhone sim trays for micro-sim. That would be really nice.
I tend to believe the iPad has micro-sim just to prevent many people from sharing the sim with their iPhone. The iPad is a much larger device and doesn't need the extra few mm of space. It should be interesting to see if the iPhone that comes out this summer has micro-sim. It could use the extra room, as micro-sims were made for small devices. If it doesn't have it, then we'll know that they did this on purpose. Otherwise good news for 3g iPad owners.
I could also see AT&T devising a way of recognizing if the sim is in an iPad or iPhone on a certain account and disabling it (heck they might already have a way of doing this since existing tethers still use the iPhone for the data connection and somewhat hides the use). It would be dumb if they disabled it since we're only using one device at a time, but we're talking about AT&T here, and more money, less service is the way to go in some parts of the USA. At least where I live service is good and fast!
