I know the developer doesn't have time to support this any longer, but I'd be willing to keep working on a FF3-compatible version of this. panpainter (at) gmail (dot) com if you're still looking for someone.
A user on forums.mozillazine.org suggested this after reading my post. I really like, but unfortunately I do not use the Bookmarks Toolbar, so this extension stops working and even if I did - it would be greater if there was a way to hardcode 1 to 9 to specific websites. Thank you. This would make this my top extension..Susan