Three curious things

1. After installing Leopard on my MacBook Pro, (text-mode) Emacs stopped working. I have no idea why. It would segfault with some kind of failure to malloc(), or something—I stopped paying attention after I noticed it wasn't running. Anyway, about a week ago, I noticed it had started working again. I have no idea why.
2. The preference I assigned to my mouse's ‘Button 4’ is no longer mysteriously disappearing. I have no idea why.
3. The other night, I synchronised my iPod and disconnected it. According to its user interface, there was no music on it. None. I plugged it back in, figuring I'd re-synchronise. That sync lasted a couple of seconds—that is, it didn't transfer 20G of music. I disconnected. My collection was intact. I have no idea why.