Ok, you really thought this through. You're right. Considering the technological requirements and amount of brainpower involved in creating this, it's hard to think that just one person created Bitcoin. It's probably a group, and I wouldn't rule out the US government, even though it seems counterproductive. One would reason that why would they create something that takes away their grip on fiat money and its power?? But does it really take away their power? If they did create it they obviously had an angle.
I thought about how they would replace fiat. It won't be easy for them to come out and say money as we know it is flawed. And that they want to replace it. It would create chaos.
Then again, it could easily be a group of individuals or corporations that got burned by the financial crisis and wanted a way to change things. Or it could be some really smart opportunistic group that did it as fun and had no idea it would blow up like this. But then they would have had massive amounts of funding and when that happens it's no longer for fun, buy on contract, a mission.
All these possibilities have confused me now. :)
Your post really got me thinking though. Thanks for sharing!