Well Gavin has mentioned this a few times that some of the believers will move onto something else
It probably will occur or is occurring as viable alternatives are appearing.
You do realize that the regulations are about business using virtual currency that falls within the scope, not Bitcoin by name. If one doesn't intend to comply with the regulations they can not comply while using Bitcoin instead of something new. If they do intend to comply with the regulations than using something new doesn't really change anything either.