Sync problems under 1.1.4

My iPhone, which is totally stock, has developed a syncing problem since I upgraded it to 1.1.4. It starts to sync fine, but at some point iTunes gives me an error dialog saying the sync has been interrupted because the iPhone has been disconnected. This isn't the case. I've tried disabling auto-off/lock, but the symptom persists. I don't actually know if it's succeeded; if I knew the order things are synced in, I could design an experiment to find out.

It's an 8 GB, with several hundred MB of empty space on it, and it's scarcely a month and a half old.

Any and all relevant comments welcome.

Tom