Rated 5 out of 5 stars
This is a great little add-on. Frankly I'm amazed that it has taken this long for the developers of Firefox (4.0) to implement a bookmarks drop-menu, and yet they still haven't realised the utility of a history/session drop-menu (crazy!). That we'll (probably) need an add-on for a history drop-menu in Firefox 4.0 is a little disgraceful really. That being said I'm very pleased that someone has taken the time to develop this, thank you Geoff Lankow!
One word to the wise though, it doesn't appear to be compatible with some themes (e.g. Strata RELOADED) as it appears to display half of two icons (forward and stop in the case of Strata RELOADED). Another oddity is that the history drop-menu isn't implemented as a separate toolbar button, but rather is tacked onto the existing bookmarks drop-menu to create a joint history/bookmarks widget. I'd prefer a separate button myself, for consistencies sake as much as anything else.