- Google may update their software at their discretion—including download and installing “new software modules”. This is a class of behaviour which is historically viral.
- Google retains certain rights to any content which passes through their browser—you retain copyrights but they may use your audio, video, photo, and blog content to their own purposes forever.
- Google retains the right to imbed advertisements into the browser itself. (Advertisements, when they exist, are currently imbedded into the pages which you visit.)
You can read a more complete article over at CNet.
Be careful to whom you give your creative works; they may not have your best interests in mind.