I'm an idiot. Don't ever, ever, ever leave out a semicolon from your plist file.
I'd been seeing this console message since the change a few days ago. I must have accidentally edited my localizable.strings file:
CFPropertyListCreateFromXMLData(): Old-style plist parser: missing semicolon in dictionary.
Anyways, I was just missing a semicolon after a string statement in that file.
Don't do that. I'm embarrassed that I've been ignoring this message