Something cool I noticed is the ability to autocomplete, not just from browsing history, but also offer suggestions from Bookmarks and Subscribed feeds.
Also like one click bookmarking. Handy for the blogger who is ever so wary about these “share on wordpress/facebook” buttons.
There are probably ways to further tweak this. But I guess I will discover that out in future.
You can get your own Firefox buttons here. (It took me a while to locate them).