Software (Thunderbird) review/questions

Hey, has anyone used Mozilla's open-source email client Thunderbird?

Check it out here.

I had never even heard of Firefox prior to Blizzard's post about using Lua's scripting language for their xml-based UI interfacing and hence, a link to Firefox as their recommended browser. Having used it and loving it (it's the only competition Opera's had in my network for the past 4 years), I found Thunderbird and wondered if anyone's had any experience with it. Good? Bad? How's the spam detection? What features does it have that separate it out?

I'm going to install it at home, but wanted to ask in here...

I've used Thunderbird and it's quite good as a replacement for Outlook Express. The spam detection is, in my experience, rather poor and marks a lot of genuine mail as spam. It also doesn't seem to integrate with Firefox quite as well as I would like - e.g. mailto: links don't open a new mail window etc. even though Firefox is the default browser and Thunderbird is the default mail client. However, I'm sure niggly little things like this will be fixed in the 1.0 releases.

There's nothing overwhelmingly special about Thunderbird, I mean it sends and receives email and allows you to sort it into different folders - what more do you want? It has standard stuff like an address book and newsgroup capability as well.