Update: I exported my entire database and did a search in WordPad. I found the offending entry in the wp_options table. You'll have to find the INSERT command and grab the option_id (first value). But here's what's screwy...I go into edit mode and change the old title to the new one (have also tried with just "Test"). I save it, go back into the record, the change is there. Then I refresh the site and it's reverted in the table. What is going on here?
It looks like all of my titles are stored in option_id 1548, so perhaps it's a standard. It's called stats_cache, so perhaps that is why it won't maintain the change?
Update #2: It appears that "stats_cache" is the cache of my most popular posts for the Popular Posts plugin, because they are in order of popularity, so the push for them is coming from elsewhere. Nothing else in the database matches the text. Does WP actually store something outside of my database somewhere (like a central DB or something)? Anyone have a clue?