I have an app that has some non-US Localizable.strings files. They appear in the project as I expect them to: there\'s a Localizable.strings object, and sub objects for \"en
This happens (apparently) when there is a Localizable.strings file in the root of the project in addition to in the individual .lproj directories. The app seems to always prefer that if it's present. The fact that it was there was likely an artifact of mucking around trying to get the localizations working in the project.
I'm leaving this question here in case others run into this issue.