Everytime I do my banking at the post office, if they aren't busy I get them to check the exchange rate for me (sometimes they even have it ready for me :-).
Today it was rp7112 - this is via the western union website that the post office orders it from and its a 'non commission' (yeah right) transaction (minimum of A$200 worth).
The currency converter on this website states today rp7763.
I have always worked on the theory of about rp200-400 difference (between that of the post office (more) and this website (less)to get an idea of 'street rate' in Bali.
Just thought this information may assist people constantly asking 'whats the exchange rate'