(BTW this ignores the fact that banks have huge political influence and will support any political attempts to block the advance of bitcoin.)
I think there's a good chance (mmm... 65.3%) that within 4 years one or more of the largest 1,000 US banks will support currency exchange to/from bitcoin for their customers.
Why would bitcoin be a threat to banks? They're really good at securely handling currency; that's a valuable service, whether the currency is dollars or euros or bitcoins.
Because every electronic transaction that occurs in Bitcoins means less revenue for them, as they are not in the middle.
They might indeed gain from more FX conversions, and I guess they could charge fees for that, but I bet they stand to loose more from lets say "intermediatary fees" than they would gain from additional forex transactions.
Isn't that the whole point of bitcoin? That it frees users from the high fees embedded in the banking system?
Btw don't Bitcoins securely handle themselves? So there is no need for 3rd party security? Or are you saying that banks might offer to protect users' wallets for them?
Gavin picked an interesting number in one of the top 1000 banks. Now this is interesting from a couple of interpretations. Does he mean *currently* 1,000 biggest banks? Or does he mean a bitcoin bank will grow so big it will be in the top 1,000? I'd assume he's talking about a company that currently is a top 1,000 bank. But even then, the banking industry is interesting. The big players have so much influence and power and a lot of the little guys- not so much. So the little guys might be tempted to adopt Bitcoin because it gives them protection against the big guys.
A brick and mortar (or even online) bank that supports Bitcoins would be great for casual users, and a point of sale instant network would also be quite good. Hell, if this really caught on, maybe banks would be the only ones that actually were running the software and we all just had interfaces to it and they still had some transaction fees, although much smaller.