Naturally, onceenabled, that sharing is also enabled across your various Netflix-ready devices, letting you see what individual friends have been watching (and letting them see what you've been watching, although you can choose to not share specific titles).
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.