Google Chrome has released their "Chrome Extensions" library with nearly 400 functional extensions... and, just like the browser, the extensions are light weight, functional and great looking (the icons animate, have gloss, and so forth). From installation to interaction, the extensions continue to separate Chrome from Firefox in speed and experience. Of course the inventory of Firefox extensions is large, but Chrome will get get there and the initial launch has content from Gmail, Bit.ly, Google Tasks / Calendar, eBay, Brizzly, etc.
For Twitter and Facebook fans, try the Brizzly extension. You can easily post and read content within the window. The user experience replicates that on Brizzly.com (such as inline media)... all from a lightweight extension atop the browser:
