The merges for Firefox 7 onto the Beta Channel, Firefox 8 onto the Aurora Channel as well as Firefox 9 onto the nightly channel has been completed. You can move to the next version within your channel (Firefox 7 Aurora to Firefox 8 Aurora) by going to (Auroa (or Beta or Nightly) Button > Help > About Aurora (or Beta or Nightly). If you want to update manually you can get the builds here: