After reading about the Thunderbird 2.0 release today I decided to upgrade. I like tagging messages and felt the need for more than just 5.
I made a list of my installed extensions and checked them for 2.0 compatibility. Don't know why, I usually don't bother, but this time I took it seriously. Good thing because a lot of the extensions weren't compatible. I decided that maybe I could do without those and downloaded TB2 anyway. In Mac OS X it's easy to simply dump the application on the desktop and run it from there. Which I did.