Yesterday I’ve seen the presentation of this new plug-in and I think it’s quite good! I’ve installed of course and indeed it’s very good! The part which I like is that it’s possible to be extended. Take a look of the video, it’s very good.

Here what the author of the original article say for Ubiquity features:

The overall goals of Ubiquity are to explore how best to:

• Empower users to control the web browser with language-based instructions. (With search, users type what they want to find. With Ubiquity, they type what they want to do.)
• Enable on-demand, user-generated mashups with existing open Web APIs. (In other words, allowing everyone–not just Web developers–to remix the Web so it fits their needs, no matter what page they are on, or what they are doing.)
• Use Trust networks and social constructs to balance security with ease of extensibility.
• Extend the browser functionality easily.

Link to the original article: Introducing Ubiquity

Ubiquity for Firefox from Aza Raskin on Vimeo.