Getting Updates

There are three types of releases:

Official releases. These are publicised via ANNOUNCE Special Notices on the Moderation Group. They are distributed via Firefox's standard update mechanism, so you should get automatically prompted to install them. They're fairly well tested.
Beta releases. These are publicised via BETA Special Notices on the group. They are files with a .xpi plugin, and they're put on the Files section of the group, here. These are first releases of new features or bug fixes, so they may have problems. You don't need to be especially technical to install Beta releases, but you may need to be patient and forgiving. Obviously, the more people who install Beta releases, the better tested the Official releases are, so please do so if you can.
Private releases. These are sent to you by mail from Edward, to debug or verify a fix for a particular problem, or to try out a new feature. They're rather like Beta releases, but for a more restricted audience.

Detailed instructions on installing are here:

See the Release Notes for detailed descriptions of each release.

You should back up before updating.