I can't help feeling that the fuss being made about 20D shutter noise is a little unjustified. I have an EOS 30 and an EOS 3, the shutter noise on the 20D lies between the two in terms of volume - true, it's noisier than the EOS 30, but it's better than the EOS 3 and its digital relatives.
Canon redesigned the shutter of the 20D in response to complaints of shutter failure in the 10D and it's predecessors. The 20D needed a beefier shutter mechanism to cope with the higher shooting rate of digital photographers. The resulting new mechanism is slightly noisier than before, but it's really not a problem. If I have to choose between a durable mechanism or less noise, I'd choose durability every time.
Jo