Google's Cloud Print takes shape in recent Chromium OS builds
While I can't tell you precisely when you'll be able to monkey around with Cloud Print, I can tell you this: it's continuing to take shape in Chromium OS. Tap Ctrl-P or hit the print option in the wrench menu, and a dialog appears which allows you to select a cloud-enabled printer. Unfortunately, without a way for me to proxify a printer right now my list is a bit barren.
You'll also be able to quickly search for other people's printers you've installed. Need to fire off a physical copy of a document to Sebastian at his office in England? No problem. Search for his email, pick his printer, and send it off (provided you've got permission, of course).
With Chrome's preferences headed to your Google Dashboard, I expect you'll see Cloud Print options appearing there, too. There won't be a way to manage printers locally in Chrome OS -- and you'll have to be able to do it from somewhere...