Chrome 21 has graduated to the beta channel. Unlike other recent releases, this Chrome actually has some things to brag about, though they may sound a bit technical.
Google Chrome 21 boasts support for getUserMedia a API which enables websites to get access to a user's webcam or microphone without the need of any plugin or proprietary technology.getUserMedia API - or webcam and microphone support
The feature is already used by whimsical apps which enable you to play around with a photo show with the webcam, add effects or stickers. There are already several app that make use of the API, but they're all on the fun side of things.
GetUserMedia though is a very important first step in implementing WebRTC, the API which promises full real-time communications support inside the browser, making things like Skype or Google+ Hangouts possible without Flash or any other plugin, everything will be standard and come with the browser.
WebRTC is not quite ready for mainstream use, but it's getting there and it's going to be a major development in the VoIP and communications world in general.
These two features are not of much actual use today, but they lay the groundwork for a new generation of powerful web apps that go beyond blurring the line between web apps and desktop apps, they start making us wonder if there is even a line there anymore.