Replacing the USD is a bit much.  It will put pressure on current systems and it might collapse Western Union but collapsing national currencies is not going to happen anytime soon.  The Internet put pressure on politicians in ways that have never been done before but it still isn't stopping their shenanigans the way people thought it would.  I remember the protest where the web site owners turned the screens black and the people thought everyone would jump.  The reality was it took 20 or 30 minutes to explain the whole thing to a Washington Bureaucrat and they would just shrug their shoulders.

The real wacky stuff comes from the people who say it will end wars.  The theory being the whole world will switch to Bitcoin and it will somehow prevent governments from spending money on war (I guess they can't use the Dark Wallet?).  The first time I heard the whole thing was that Free State Radio who broadcast parts of the first big Foundation conference.  They played commercials claiming that all government employees were murderers.  That means janitors, social security workers, astronauts, etc. are all murders.  They also talk about 'government" as if is one thing all coordinated.  They played an excerpt from the Onion on the show and I could not tell the difference between the Onion stuff and the stuff they claimed to be serious.  One person who comes from this group often claims on podcasts that Bitcoin is increasing "exponentially" and that there is this "huge" Bitcoin economy.  The real reason is that almost nobody listens to their stuff so they have to latch onto a technology and claim that people who use it agree with them.