Will the iPhone work in Europe, Asia, etc?
Yes, the iPhone will work overseas, and not just in Europe and Asia. The iPhone is a GSM (Global System for Mobile communication) phone. GSM, which uses narrowband TDMA, was first introduced as a standard in 1991 and is now in place in over 100 countries.
Access to receive and place calls from outside the United States will require additional services from AT&T/Cingular, which you will need to arrange with them before your phone will operate in such a fashion, but the phone is perfectly capable for worldwide use.