gordon,
true only to a certain extent. Human memory is a subejctive thing. Ask four pilots and you will get four slightly (or even significantly) different versions of the same event.
Modern CVRs are digital and record onto heat- and shockresistant solid state devices. Its just that appearantly there is still not enough space available. (In a quick search around google, I was not able to find what CVRs Qantas' A380s are fitted with)
regards.