Provided you have renamed the network interface names in baselayout you should fix the documentation as well.
As I understand it, network interface names are given names like eth0 and wlan0 by the kernel, then they are (by default) renamed to something ("predictable") based on their physical location on the hardware buses of your box by udev. This means that different hardware setups give different names by default, so no "correct" name can be given in the handbook. The old naming is however still available by making simple configuration changes as documented on the wiki.[1] The "old" naming is still default if eudev, mdev or a static /dev is used. My humble opinion is to keep the "unpredictable" names in the examples, but better document the high likelihood of interface names being different. A section on how to disable the renaming would be nice, but is not necessary. 1: http://wiki.gentoo.org/wiki/Udev/upgrade#udev_200
Our documents already state that the names can/will differ for installations, and that for the handbook we'll use eth0. Also, when necessary, we re-iterate that eth0 is an example and that the reader needs to substitute it with the proper interface name.
