Anyway, I see what you're saying and it makes perfect sense, if the title actually existed in iTunes. The podcast has completely disappeared from my computer except for the .xml entry. It really makes no sense. The actual file isn't in the specified location nor is there an entry in iTunes itself under Podcasts.

My Apple TV was reporting the same erroneous entry for that podcast (obviously because it uses the same .xml file).

I did, however, fix the problem and felt it was important to post my solution here. Warning though, it was a royal pain. I moved the following three files out of my iTunes folder (save them as a backup incase you change your mind):

1. iTunes Library (where I believe the problem resided) 
2. iTunes Library Extras 
3. iTunes Library Genius

Then, once I reopened iTunes, it was like starting from scratch. It recreated all three files. All my music and playlists were gone. I painstakingly added all my music, movies, podcasts, playlists, Apple TV, and iPhone back into this "New" iTunes library. And viola, no bad entry in the .xml file.

Thanks, 
Josh