Google Chrome Extension Gallery treads lightly on copyright issues
Unlike Mozilla's add-on site for Firefox, it appears as though things are going to run in a slightly more Apple-esque fashion.
Developer Deepesh Agarwal submitted a Chrome port of his Firefox add-on Easy YouTube Downloader. Google declined to approve the extension, saying "Unfortunately, there are a few cases where legal restrictions or contractual obligations prevent us from hosting an extension(*). One of those cases is with certain kinds of video downloaders..."
That policy is clearly spelled out in the TOS, of course:
Hey, this is Google's baby, after all, so I'm not really surprised they don't plan to publicly exhibit extensions designed to play Google-hosted content offline (and beyond the reach of AdSense and Analytics). On top of that, Google has been careful of late when it comes to playing nice with rights holders.4.4.1 You agree that you will not engage in any activity with the Gallery, including the development or publication of Products or other materials, that [...] enables the unauthorized download of streaming content or media.
And don't forget, .crx files can be installed from any old website. Chromeextensions.org has been up for months and will no doubt be the place to go for non-sanctioned extensions. Like video downloaders.