I use it, but not often enough to make a real dent, my issue is that it isn't integrated into the browser, it's a feature that with some UI tweaks could really make everyone a poweruser, the concept itself is powerful but the un-extensibility of chrome (and browsers in general) holds it back from being a true first party app.

Agreed. And it's one of the reasons why I dislike the trend of the browsers being increasingly locked down and non-modifiable. Soon, even to recreate this plugin you'll have to run a parallel fork of a browser.