Rated 4 out of 5 stars

I also like the add-on very much, but I completely agree with amystko: what is missing is a simple way to filter by the tags.
However, a way to make it a bit more comfortable is here:
http://www.ehow.com/how_4756668_use-thunderbird-things-done.html

This review is for a previous version of the add-on (0.8.12).