I got a piece of bulk mail yesterday with one of those yellow "please inform sender of new address" labels on it. The mail had been addressed to my old street address, but in Richmond, VA instead of Redmond WA. It seems like an understandable enough mistake in hindsight, although it does make me kind of wonder what kind of process was at work that required human transcription from one large database to another.
More striking to me was that the post office still got it right, which indicates that their new-address database is more extensive than just a simple lookup based on supposed target address. It seems very unlikely that there's a Red-Wood road in Richmond. In fact, I've been to Richmond, and I don't remember there being one. I'm kind of curious now, if someone were to address mail to me at a totally non-existent address, would it still reach me? Before yesterday, I'd have said no. Now, I'm not so sure.