In a post over at the Chromium blog, Google explains how printing will work with Chrome OS (or any web-based printing, whether it's from Google Docs, your phone, or your Chrome browser) and—they hope—get rid of the hassle of printer drivers once and for all.
Rather than rely on the local operating system (or drivers) to print, apps can use Google Cloud Print to submit and manage print jobs. Google Cloud Print will then be responsible for sending the print job to the appropriate printer with the particular options the user selected, and returning the job status to the app.
In a lightweight, browser-only operating system like Google Chrome OS, the regular plug-and-play printing model isn't going to work, so Google Cloud Print aims to fill this void. The service isn't finished at this point, but the code and documentation of the open source project is. [Chromium Blog]