I have my explanation why the drop happened - price has gone to $43 and some big guy was playing with a big 50k BTC wall at the Gox, trying to set a SCARE WALL at $43, but accidentally typed $34 instead and kaboom! He's now hanging from a ceiling somewhere in a Singapore hotel room and we have had some cheap bitcoins, all went well.
Heh, if that's the case good riddance then
I always felt it is good for long term health of bitcoin when someone dumps like that as that will make it harder to crash in the future with single push of a button.
EDIT: If you look at height of the bitcoin volume during the crash , it has been getting smaller and smaller. One reason for that it less people now are holding large amount of bitcoins than before and bitcoins are getting distributed to more hands that don't get scared quite easily.