There are at least two entities who have critical pieces of data you do not. And that is dwolla and mtgox. Both of them have hard facts on amount of other currencies entering and leaving the trading pools, both over time and immediately. Mtgox has precise figures on all currencies, and dwolla has a picture only of dollars -- however, they have that sooner.
Since neither of these entities is regulated in any way shape or form you may be trading against someone with a clear picture of trader sentiment while you have to wait while various patterns emerge on the chart.
In fact, it is doubly advantageous to mtgox vested interests to delay posting of new funds to accounts long enough to establish their own position in the market -- the swings in price could be magnified, and price swings cause more trading.
Might want to keep that in mind when choosing your target time frame, or evaluating day trading vs buy and hold.