ilter: i don't know the state of the svn repo but looking at the bottom of https://gitweb.torproject.org//tor.git
you will see four different "heads" (or branches), where "master" is what svn people call "trunk".
ilter: bleeding edge is on "master" and stable releases are on "maint-0.2.1".
ilter: if you look at the "tags" section of that same page, you'll see tags named tor-<version> and sometimes tor-<version>-alpha. these are releases, so to speak.
ilter: the 0.2.2 series contains some code that 0.2.1 lacks and is called unstable while 0.2.1 is the stable series of releases.