According to RIM, the 8830 WILL function over seas, without a SIM. It will always search for CDMA carriers. It will be an issue of VZN & Alltel ALLOWING it do connect...and at what price. If you pop in the SIM card, THEN it will only connect to GSM networks.
I'm in need of a "12 step Program" to help me with my Crackberry Addiction!