Fudzilla spoke with dozens of contacts in the graphics world and they heard the R600 GPU hasn't been shrunk to 65nm or 60nm. It was designed as a 80nm chip and they heard a shrink would require a complete redesign:
ATI doesn't have the time for it and we don't believe that AMD / ATI could get away deceiving dozens of its partners and OEM's with news that R600 is 80 nanometre, until it suits them.
R600 was and is 80 nanometre and when it launches it will be 80 nanometre. Remember G80, Geforce 8800 series is 90 nanometre and it still runs great. So if you do you homework well even the big chip works well.
Sorry to disappoint you but R600 will be re branded and probably cheaper than everyone expects but its very unlikely that we are waiting for G80 killer.