It falls in line with other speculation like, exchanging closing during a sell to prevent a full sell-out (gox did it twice) and coinbase has a way of it's own.
But the problem with this one is volume.Yeah there are 200k unconfirmed transactions but
-how much is spam
-how much is close to dust level
-how much is just people moving around coins
To really make a dent in the markets you would need volume. And guys who can't afford 15$ per tx would not be able to do it.
Some Gox-like scenarios are happening whenever the price hits an all-time high. Witnessed and experienced it firsthand and it's kinda disappointing. As for the transaction volumes on the network, a huge portion of it are not even significant to be accounted on the daily trading volume that really moves the price. The effect is so little to be counted, and not all of those transactions are even headed to exchanges.