We package GNOME3 extra apps for Ubuntu 12.04 and newer.
To join this team go to #ubuntu-desktop and introduce yourself. To be a member you should have good experience with updating packages. If you are still learning, the best thing is to propose merges into the package branches (lp:~gnome3-team/package-name/ubuntu) and ask for help in #ubuntu-desktop.
Discussion about GNOME3 and Ubuntu should be done on the Ubuntu Desktop mailing list: <email address hidden>