Mt. Gox is NOT the same as Bitcoin.
Again, forget Mt. Gox (wow did they fall over tonight) - I'm mean to say: Nobody 'normal' will feel safe investing in a currency that's so vulnerable to volatility..
For the record: I don't give a damn, I'm sticking with this for the long run, better or worse.
Volatility isn't an issue when there's a general up-trend. Look at Bitcoin's history to date - the safest move so far would have been to buy early and hold indefinitely. Gold has functioned similarly over the past 10 years and has been quite volatile itself having experienced 10% swings in days and 30% swings in weeks/months. It's interesting to note that although the value of gold has been referred to as "volatile," it is often described as such in relation to the dollar rather than on its own accord (i.e. the value of gold is determined relative to the "volatile" price of the US dollar).