Releases and what is the workflow

Hi All! Dev Guide page about releases is almost empty: http://openjdk.java.net/guide/releases.html Are there some drafts explaining currently existing releases and their workflow? If yes - please give some links. If no - please explain in few words, are changes from jdk7u2 backported to jdk7u, are changes from jdk7u backported to jdk7, what means gate and what means development in repositories list, and if I want to create a fork and keep it up to date through u2-u3-u4 and so on - what release is the best for me? Thanx!