One of my co-workers mentioned something about thunderbirds new features, i thought this is an excellent time to break my mail client! so promptly looked up installing the new thunderbird.

My work box is Ubuntu, so here’s the easiest process to get Thunderbird 3 installed

I used Ubuntuzilla to get the latest packages http://sourceforge.net/apps/mediawiki/ubuntuzilla/index.php?title=Main_Page

echo "deb http://switch.dl.sourceforge.net/project/ubuntuzilla/mozilla/apt all main" | sudo tee -a /etc/apt/sources.list > /dev/null
sudo apt-key adv --recv-keys --keyserver keyserver.ubuntu.com C1289A29
sudo apt-get update
sudo apt-get install thunderbird-mozilla-build

Then because i wanted my old profile i started it with the profile manager

thunderbird --profileManager

I added a profile, then pointed it to ~/.mozilla-thunderbird/profiledir which was the old schema. The new place is ~/.thunderbird so in hindsight i probably just have copied over the profile to there before using it. No biggie though.
It crashed a few times with various errors as I updated plugins and other things, but after the 3rd time it just worked.
All i can says is ‘wow’ very cool! I have a global inbox for all my emails, and then an inbox for each account individually. It has tabs and some brilliant UI looks.

Give it a go yourself and see what you think!