Bitcoin is a Bubble is no joke; Bitcoin's History is full of them.
Most notably are the 5 Mega bubbles ending almost an order of magnitude more valuable after the "resulting" crash.
There have only been 2 noteworthy teething bubbles where a new order of magnitude has been tested.
It's clear Bitcoin is growing, in value with each bubble, but the question you need to answer before investing is, is the user base growing?
Easy to answer if you're investing in the Bitcoin Protocol for the first time, not so easy if you have been through a bubble or two!
A layman's guess is Bubbles 1, 2 and 3 saw an increase of adoption proportional to the growth, possibly Bubble 5 saw the user base grow as well. The bubble 4 in my opinion was largely a narcissistic one, as it was followed by the 2 teething bubbles that saw the necessary increase in adoption.
Predicting where the next bubble will end up is all about predicting the growth of the user base adopting the protocol / aka. investing in Bitcoin.
I think it is still too soon to know what's about to happen, but it is Fun times ahead.