Case in point: There is a 2,000-person Bitcoin event in NYC today and tomorrow, Inside Bitcoins, at the Javits Center no less. But don't worry if you miss it, the event is scheduled to travel the globe with stops in Hong Kong, Melbourne, Tel Aviv, London, Singapore, Berlin, before landing back in NYC a year from now.
In the keynote, Circle CEO Jeremy Allaire estimated 2,000 startups globally are working on crypto-currency products and services. That alone makes it more than a fad (bubble perhaps, but not a fad). There is no putting the crypto-currency genie back in the bottle. The technology is too compelling. The demand for alternative stored value is so huge that I don't see it being regulated away, at least outside the west.
Relevance for Banks: U.S. financial institutions will steer clear until regulatory uncertainties are cleared up. While regulators ARE paying attention (even the IRS recently weighed in), don't expect banks or credit unions here to be accepting Bitcoins for deposit anytime soon.
However, I do expect U.S. prepaid-card based "near banks" (Moven, Onbudget) to work with Coinbase and others to make it easy to move Bitcoin value onto their cards (see note 1). For inspiration, check out the Bitcoin debit card launched today by Hong Kong-based Cryptex Card (press release).