Bitcoin has been off the radar for the SEC, but as it gains notoriety there will certainly be an interest in regulating it.
Imagine that tomorrow Bitcoin gets really big, it isn't crazy to think that many people will be worried about having all their money in the computer they use everyday and is connected to the Internet. Then some companies start offering a service which lets you deposit your bitcoins and they assure you that they won't get robbed and if they do, they will be held responsible for that. Oh, and they require you to have a verifiable identity for your account since that helps to prevent fraud. They just ask a monthly fee for the maintenance of your account and a small fee for every transaction you make through them. You have in front of you something similar to a bank.
So, if you have to pay bureaucratic costs of regulation, and institutions like banks for Bitcoin, then it's not that different from the money we are used to. The one which also hasn't intrinsic value and for most of us is just a number in a computer anyway.