Even after disabling Keychain sync, my laptop still exhibits weird behavior that I suspect is related (it was never problematic before I had MobileMe):
- Mail only remembers my IMAP and SMTP server passwords until it’s closed. Every time I reboot, it asks me again. I use the same servers, settings, and passwords on two desktops with no problems.
- NetNewsWire loses its sync-service password every time it’s launched.
And while it’s not Keychain-related, Contacts sync still has some people who just generate weird little conflicts very frequently on little stuff like buddy icons and which number is the primary (and these are contacts that I never edit).