That there wasn't really a fundamental cause for the price to fall so in the first place?

Edit:  I'll elaborate because I've been pondering this one and would appreciate your thoughts on my analysis/hypothesis/fantasy of what happened and why:

From recollection there was an ask sum of around $16 million USD just prior to the collapse.  Despite this the heavy volume of trading didn't kick in until it first looked like the dip was bottoming out so I'm going to hazard a guess that much of that ask depth (well as much as could be managed given MtGox technical limitations) was removed as the price was plummeting therefore it didn't need much panic or speculative selling to drive the price down pretty low.  There was then an immense amount of buying at the first mini recovery until it became obvious for whatever reasons the bears weren't done yet so once again buyers stepped back and withdrew to watch and see how low it was going to go.  With MtGox as (to date) the main price driver out of action there was no need to rush, no need to be afraid to miss the boat on buying back in and also it probably took some time to reassess how they judge the current market, many for the first time looking at prices over multiple exchanges prior to deciding how to play it.

So a relative few in number with not an enormous amount of money had never seen the market go down and had bought stupid only to lose their nerve as soon as it looked like a serious downturn.  This was exacerbated by a combination of bitcoin-flush speculators who have been waiting for a decent scalping opportunity for some time and the lack of a realistic margin market that could have calmed the waters.  Then there's the whole trading blind thing which I'm guessing meant loads of people have simply stayed out and watched relatively few people take the market a very long way.

I would like this to serve as a lesson to all who come to Bitcoin for the first time in the forthcoming months and for those who were in the MtGox verification queue that the market can fall too and subsequently will be a bit less rash with their purchasing.  This should mean however long it takes before we pass where we were at peak yesterday (I'd be more surprised if it were very slow than very fast) the set of circumstances that led to this are unlikely to happen to the same degree again