Very useful addon. Would be nice to be able to leftclick on a result to view it directly, instead of doing rightclick->view image.

Edited to add: Awesome, thanks!
Edited after testing:
Works fine! It seems that quite some webservers send headers/mimetype or something that cause firefox to display the save as dialog instead of displaying the image. Not the addon's fault ofcourse but maybe there is a way to prevent this as the browser does find a way to prevent the save-as dialog when doing middleclick to open in a new tab or rightclick->view image. If nothing else works a solution could be to generate html with just an image tag that shows the image at 100%.