One click masterpiece

You must get this. The key feature is that it handles the SECOND batch of translation. Genstrings can do the first, but as soon as you need five new strings added your life gets complicated. But this app is just drag-project, drag-project, hit button. It does the diff and merge for you. It even works if you didnt use it for the first translation pass. Its a thing of beauty.

OneOfManyGrahams about Localizable Strings Merge