I think I finally figured out the problem I was having with syncing my iPod via Amarok. The key seems to be that some other KDE services need to be running in order for the iPod to be fully identified properly. Without those services, it shows up but gets treated like a generic, unidentified iPod and there’s no history for it to sync against.
The thing that made it inconsistent was that I wasn’t always running the full KDE environment. Sometimes I’d export it via X11 to my laptop, and after the recent reinstall I was running Gnome instead of KDE for a while. I should be okay as long as I keep using KDE as my desktop and always run it at the console, which shouldn’t be too big a deal as it’s about the only thing I use the console for nowadays anyway.