Once tethering is enabled, connect your iPhone 3G, 3GS or iPhone 4 to the Nexaira BC2 Router via your iPhone USB cable and within a few seconds, your iPhone will indicate that it is in "Internet Tethering" mode.
And to be clear, the first versions of the Playbook in fact will reach the Internet either via WiFi, or through Bluetooth tethering to your BlackBerry, though the company also plans to offer a broadband wireless version of the device via Sprint later in the year.