Rated 4 out of 5 stars

I've had this extension installed for months, and while it works as advertised and it's pretty cool, truth is that my Google searches rarely have a Wolfram-Alpha equivalent, so I've only ever seen the W-A results on the right side of the screen a handful of times. But that's not the extension's fault. So I say good job to the author for the idea and to readers of this review who haven't yet installed the extension, it's worth a look, at least, so give it a download and give it a try.

One minor complaint: Please don't force users to add an icon to their statusbar - provide an option for statusbar icon OR toolbar icon. Thanks.

This review is for a previous version of the add-on (0.9). 

Option to hide Statusbar icon

Hi RenegadeX,
Thanks for the feedback. It seems Wolfram Alpha is gradually adding more content but yeah it doesn't have results for a lot of categories and could do with a lot more.

About the statusbar icon. There's a new version (1.0) available now that adds an option to hide the statusbar icon. You can get it from this page now https://addons.mozilla.org/en-US/firefox/addons/versions/12006 or wait until it is approved by Mozilla and it will update automatically.