Oh yeah.....this is nice! Rated 5 out of 5 stars

As someone who does a ton of web surfing this extension has proved to be one awfully convenient add-on. Being able to preview a link by a simple mouse-over is wonderful. With this extension you can also email any link very easily. On top of that Cooliris Previews also allows you to resize preview windows, lock preview windows in place, and even temporarily store thumbnails of those preview windows in an adjustable size slide out window. You can also change the amount of time it takes the mouse-over to activate the preview. If you haven't seen this extension yet I HIGHLY RECOMMEND you do so. It's really worth a look.

This review is for a previous version of the add-on (2.1).