Install too quiet for sysadmin (Score 1)

Chrome sure installs quietly - doesn't require admin rights and didn't even invoke UAC on Vista, and that is for installing an app that will be used for web browsing, not a very good thing in my book. It installs into the user-owned directories with minor registry changes which begs the question - how secure is it against a worm that runs under the same user privileges? There is nothing limiting its potential interaction with the code or config files for Chrome. I am looking for more info on this, feel free to point me to any helpful links.