And now for something completely different...
For the past couple of weeks, I've not been able to sync my iPhone. What happens is that I plug it in to my computer, start the sync and two hours later, iTunes shows it's about 75% complete. After some googling, I tried a few things like deleting old backups, changing some settings, etc, but nothing seemed to help. Tonight I decided I'd try deleting all the photos and videos on my phone. Sure enough, that did the trick. I'm now able to successfully sync in a reasonable amount of time.