The users iTunes library is one of the default destinations for the new mediaGalleries API in Chrome
The mediaGalleries API is what Chrome and Chrome OS use to access images, videos and audio that is stored locally on the device. This means your media can be treated the same way online media is by Chrome apps, making them available for your viewing and listening pleasure right inside the Chrome browser.
A quick posting on Google+ from François Beaufort, everyone's favorite Chromium Evangelist, let everyone know that recent code changes mean that your iTunes library is one of the APIs default locations (your iTunes folder has a system-wide variable so it can be found by any program), meaning that music and other media you've stored there will show up automatically after a local media scan from Chrome -- with your permission, of course.
Why is this important? Imagine the Google Music
website web app, redesigned so that you can play local music files as well. Or the Google Movies and TV Chrome app, or the upcoming image viewer. All your current media could be easily made available right inside these web apps from Google, or other third party extensions and Chrome apps. We're confident that Google knows that Chromebooks need at least a little bit of ability to play offline content, and building it into an API means that desktop Chrome users can benefit as well, with access to a possibly hefty iTunes library full of DRM-free "stuff".
You can check out an example of what they're doing currently if you're running Canary by loading up this Chrome app from Google's github.