Thanks again, theymos!
Speaking of long-term concerns with Bitcoin, have you read this critique?
On the fact that Bitcoin has a Kill Switch; and how to disconnect it.
http://www.loper-os.org/?p=1009The basic thrust is that a very few individuals own the vast majority of Bitcoins, that they actively conceal this fact through obfuscation, and that they will "kill" Bitcoin at some point by flooding the market. (This last claim strikes me as rather remote - what possible gain could they hope to achieve?)