Dogecoin changed my perspective on cryptocurrencies personally. I battled with the concept of altcoins: why they have value, and whether they aren't just taking away the value from one cryptocurrency. The change it instilled is that crpytocurrencies can simply function as an investment in an any idea/concept/theme. So far all coins were "arbitrary", centered around vague ideas: 'feathercoin', 'litecoin', etc. Some had technical improvements, but its power were just a belief. Dogecoin is the first coin where there is a much more clearer purpose behind: that of the doge meme. It means we will start seeing a cryptocoin for anything and everything. It's a way to create a world of public shareholding... of anythin.
Memes are, almost by definition, temporary fads. That seems like a terrible thing to build a currency around. What happens when people get sick of Doge?
The fact that you have to ask that question is part of it. I really need to do a writeup on it, I've been too busy.