The application normally has to be reviewed by the department concerned and they often do this at weekly meetings. They have to then appoint a possible supervisor and second supervisor, and academics being academics, they may take a while to do this. Often if you have had contact with your potential supervisor, then ask for some feedback. I was verbally told before I applied and that made the process a lot less nerve jangling!! Worth the wait though - and remeber you are the client so be persistant!!