The big news out of Google
It sounds revolutionary for smartphones because they haven't been equipped with much printing prowess to this point. Resaerch In Motion
Apple is the only major mobile player that has anything close to an official, transparent printing solution. But the AirPrint feature requires printers that can speak the AirPrint protocol, all of which currently come from Hewlett-Packard
So what Google has done here is to solve a cross-platform problem with a Google-only fix. The only Cloud Print app so far is Gmail, though it'll work in any reasonably modern browser on your hardware of choice. I'd assume that cloud printing would come later to Google Docs, maybe to Google's famed search services, and perhaps even to a public programming interface for other developers to use. But now it's just a very limited proof of concept in need of much spit and polish.
Beyond the narrow usage case, the service doesn't let you set a default printer and warns that any printer you remove from the management console may be reinstalled against your will. Not slick.
Moreover, the announcement reads as if every Chrome browser running on Windows can act as a print server today with Linux and Mac support coming later, but you actually need a beta or developer-grade browser in order to use it. Yes, it's a temporary issue given the speed of Google's version march, but it's annoying not to see what you thought was promised.
ZDNet writer Sam Diaz calls Cloud Print "a 2001 solution to a 2011 problem," and the unpolished product sure feels badly aged at launch. Will Google refine it with rapid iteration, or will it give up and leave it for dead if nobody needs it? Only time will tell. The best Google can do to speed up adoption is to make that programming interface available, stat. If this is just a tactic to snare more web users into a Google account, Big G needs to try harder.