We uncovered a really, really nasty bug yesterday. I don't want to go into all the details (it would take all day) but it relates to versions 1.5 through 1.8 of the Firefox TrailBar. Internet Explorer users are not affected. If you installed the Firefox TrailBar for the first time with one of these versions then trails were not recorded properly. This has now been fixed in the 1.9 release available here: http://trexy.com/trailbar.html.