I really want to use this widget, as the interface is very nice, but after months of use I've given up. One component or another is always broken it seems, and they are slow to fix it. It's free, so I can't exactly blame them, but it's just not reliable.

I just installed a new package tracking widget called "Package Tracking" which I got through Apple's Widget site. So far, so good. Not nearly as pretty as this one, but it works. You can also check it out yourselves from http://codeadrian.sitesled.com/software/