Google, I am dissapoint Rated 1 out of 5 stars

Picture overlay icon ignores the preference to hide it. (If you have adblock plus you can hide the overlay with the filter rule ##.sbi_search.)
Addon uses 100% cpu when moving your mouse around over images.

Looking at the source it binds mousemove and removes then reinjects the the icon every time the mouse moves a pixel. (Couldn't you use mouseenter instead?)

If mousenter doesnt work for some reason then at the very least add a check to the top of the handler like below:
if ( currentImage.is(imagesearch.sbi.active_image) ) return;

This review is for a previous version of the add-on (1.0.7). 

Thank you for your feedback. We have submitted an experimental version 1.0.8 to address the excessive CPU load issue.

EDIT: We have just released v1.1.1 which reduces the CPU usage by this extension and improves the user experience.