I've always been a big proponent of the idea that BTC and major alt coins will need to become something more than investment vehicles and ways to transfer money if they are to become truly mainstream.
When I can walk down the street in my town and there are "Bitcoin accepted here" on a few shop doors, that's when we've moved on from just being a "fringe novelty." And when players like Starbucks, Amazon, eBay and others accept BTC as a form of payment, it's also going to make it that much harder for governments and regulators to "outlaw" cryptos... you don't want to anger your biggest taxpayers!