One of the telltale signs that you're holing a 3G version of the iPad is the matte black plastic strip that runs across the back and wraps up around the top edge. This plastic panel makes it easier for the iPad's internal 3G antenna to grab a signal.
The iPad 3G's settings menu includes two additional options not found on the standard iPad. An "Airplane Mode" switch at the top of the menu will temporarily disable the iPad's 3G capabilities. A menu selection for "Cellular Data" allows you to set up and manage your 3G data plan.
The iPad 3G comes with one little accessory not included with the standard model: a glorified paper clip. This little poker tool can be used to eject the micro-SIM card embedded in the side of the iPad 3G.
Users can subscribe to a 3G data plan directly on the iPad 3G. Credit card and cardholder information is relayed directly to AT&T, cutting out Apple as a middleman.
During the account set-up process, users can choose between a $14.99 with a monthly cap of 250MB of data, or an unlimited plan for $29.99 per month. The 3G service is offered with no contract and can be canceled at any time, without penalty.