Have you tried to localize your projects and then discovered that the Localizable.strings files get overwritten each time you run genstrings, making you lose your already translated files?
I just couldn't accept it and made a script that allows you to always keep your previous translations, by merging the new strings with the previous ones (already translated). With this tool you can translate as you develop.
I hope it helps someone.
Incremental localization on XCode-based projects