The market cap has increased by that much, but 200m$ wasn't bought on the exchanges, just a touch over a million dollars
It would be nice if Mt. Gox were to release another one of their "Transparency" reports. The last one (August 2012) reported roughly about $5 million in deposits (in some 30 day period) and from the publicly available trading volume numbers for July there was trading about $25 million traded at all of Mt. Gox over the same period.
So if that ratio were to continue today (even assuming 100% of those deposits were new inflows to make purchases, like buy and hold, of bitcoins then there are inflows of 1/5th of the trading volume. In February there was under $50 million USD worth of trades on all Mt. Gox markets combined and Mt. Gox represents maybe 80% so, let's say there was $60 million USD of trading on all markets in February. If that 1/5th metric holds (a big if, but it is all I got to work with), that would mean there was only $12 million of new buying needed to increase the exchange rate from $20.51 to $33.38, or by about $140 million increase.
So put another way, an inflow of just 5% of the previous value of all bitcoins resulted in a 60% increase in the exchange rate.
And thus a $200 increase in the exchange rate took only $16 million of new buying.
That's not to say these cash inflows are not significant but what isn't being appreciated is that this $200 million in increase in total dollar valuation/TDV ("market cap" is a misnomer) will vaporize when all these people who in aggregate believe they can tap into this $200 million of wealth and the majority of it simply never existed,
Which makes the old saying even more timely ... nobody ever went broke taking a little bit home.
