Why exactly is Bitcoin rallying? Nothing has changed.
Incremental changes have a cumulative effect. Ukraine, Greece, Euro weakness, South America, remittances, regulated exchanges and ETFs, Paypal support, Bitpesa, messaging apps, etc etc.
The rally has solid momentum now, so nothing changing means UP.
Also if you have the right connections and listen into the right places you get to hear some very interesting insider information. Serious players have been accumulating lower down and the coin supply has dried up. Couple that with the fact a lot of people think that 160 was the bottom makes for fireworks.