It’s hardly “rooting” since Google ships the devices to knowingly allow root access, but first-time rooters might breathe a sigh of relief they don’t need to go to great lengths to get the job done. This doesn’t change anything though: you could still very easily break your phone and anything you do to your phone is at YOUR OWN RISK. We are in no way responsible.
However if you succeed, rooting will allow you deeper access to the OS for things like backing up apps/games/settings, altering application and system icons/themes/designs, overclocking and tweaking system resources, and more. For those who like to tinker, I suggest you visit our Galaxy Nexus Root Forums for more!