The imported address I used to send the BTC was deterministically generated on brainwallet.org using a not-so-strong passphrase (after all, this is just a test). Is it possible that someone else in the vast Bitcoin universe used the exact same not-so-strong passphrase and just got an unexpected donation of 0.01 BTC?
you found the answer to your question. yes, you have been robbed.
Confirmed. A respected Bitcoin security researcher was running a
POC brainwallet bot and nabbed my bitcents instantly. He DM'ed me and returned the funds. Seriously righteous thing to do.
- Dave
Well, good news then! You are lucky. Harvesting brainwallets is big business now.