The iPhone got dissembled pretty much just min. after it launched on Friday. One interesting detail is the fact that to remove the AT&T SIM card you do not have to open up the iPhone.

iFixit reports in their iPhone dissection reports that you just need to poke with a bent up paperclip inside a whole on to of the iPhone (see photo). The SIM card pops out from the slot next to the hole.
The iPhone needs to be activated first to actually enable several features on the iPhone itself.
Now the hacker community is sure already hard at work to figure out how to unlock the iPhone. They need to hack the activation process and the SIM card to actually get to a completely unlocked iPhone.