Bel - we did our birth plan after I got handed a piece of paper from the midwife at the 36 week appt.
I gave it back at the 38 week appt, and they barely looked at it.
Apparently at Geelong, they aren't really referred to - at least thats what Deb said. Even when we looked through it, the midwife said its just to keep you thinking about things.
I was very vague about things like pain relief and what positions for birth - better to be vague than miss out when the going gets rough! I have said I want to try heat therapy, showers, and depending on how things are going, a water birth. I guess it will depend how things pan out though.
One thing I would say is important to specify is visitors and students. Definitly be clear on how you feel about that!