According to Minsky's theory of financial instability there are 5 stages of a credit cycle (Bubble). One can take a read and see if the events that took place matches with his theory.
Compare it to the bubble cycles of events such as the 2002 Dot.com collapse, or the 2009 Housing bubble in the US that lead to the sub-prime crisis.
A crude way of understanding a bubble is when the price far exceeds the underlying/intrinsic value of the asset.
However, the world has yet to be able to identify if bitcoins is a commodity or a currency. Much less identify a method to measure its true value.
Pro bitcoin camp has been saying that price itself, is the market value, based on free market supply and demand (Worth whatever amount people is willing to buy and thus the theory of infinite value). Therefore, it is not a bubble as price does not exceed the value. Somehow similar to how we evaluate our properties.
As Kenpachi82 and dexboi mentioned, there is no way however those governments will sit by idly, letting something with the potential to disrupt the global economy to run amok. They will surely intervene in the attempt to control it.
Next, seeing how the price rises so dramatically, it will be hard to believe that there is no manipulation involved. Once such major player(s), aka the whales, decided to rake in the profit, I can imagine the dive to be as exciting as bungee jumping.
Lastly, as the value is based on the confidence of the owners/investors of bitcoins, we will know how much faith they have when a recession hit.