The SIM slot is gone. According to Apple, the SIM card and SIM tray were the only user-serviceable parts in the AT&T iPhone 4. Apple now says "iPhone does not contain any user-serviceable parts." We believe you have the right to repair your own hardware, and we'll have a repair guide available right away.

We believe the additional break in the antenna enclosure on the right side of the phone is a result of the switch from GSM to CDMA. An antenna's operating frequency is directly dependent on its size and geometry, so the change-up required an antenna overhaul.

The AT&T GSM iPhone has three differently shaped antennas, which enable the phone to communicate on UMTS/HSDPA/HSUPA (850, 900, 1900, 2100 MHz) and GSM/EDGE (850, 900, 1800, 1900 MHz).

The CDMA iPhone, which has four antenna segments (two "U" shaped pieces at the top and bottom, and two straight bars along the edge) only needs to operate on 800 and 1900 MHz for CDMA EV-DO Rev. A.

Both phones use 2400 MHz frequencies for Bluetooth and 2.4 GHz for WiFi and the 1.575 GHz frequency for A-GPS.

Only time will tell if this new antenna design helps combat the reception problems reportedly plaguing AT&T's GSM iPhone 4. However, there is no reason to expect that it would as the problem reportedly does not occur with the GSM iPhone on other GSM networks around the world.