It's a computer, not a smart phone or a tablet. And the Chrome OS is built on top of Linux, which has proven quite bulletproof to lawsuits by scammers and patent free-loaders, even those with secret backing from Redmond.
Android is built on linux as well, and has been a magnet for lawsuits. According to this link, from 2011, 25 patents from Microsoft have been used in various suits:
And others are cashing in as well, like this company that was awarded $5 million from Google just a few weeks ago:
http://www.engadget.com/2011/04/21/google-ordered-to-pay-5-million-in-linux-patent-infringement-su/
I’m not saying that lawsuits are good, but since Linux is a clone by nature it should certainly expect more. And the new one from Oracle against Google is a doozy, let e know if you need a link to that one as well.