Rated 5 out of 5 stars
Please, make this extension compatible with Firefox 5 - right now it generates broken delta pages which lack CSS styling and images (I'm using UpdateScanner with Russian Groupon: http://www.biglion.ru/)This review is for a previous version of the add-on (184.108.40.206-signed).
Try the beta release
There's experimental support for Firefox 5 in the latest beta release. Click "Install Development Version" from the main addon page (https://addons.mozilla.org/en-US/firefox/addon/update-scanner/)