Rated 4 out of 5 stars

Not having a calendar function was one of the drawbacks of Thunderbird for me. This extension helps solve that and it goes a long way to correcting this problem. Overall, I like this a lot, especially with the Provider for Google Calendar extension. Problems: tasks don't appear on the calendar, does not import from Outlook directly (got around this by using Plaxo, then synching with Google), and cannot drag an email to a date to create an event.

This review is for a previous version of the add-on (0.5).