In previous versions the language file for frontend and backend were the same. Obviously this was not a really good thing - making changes to the frontend file meant that we need to update the backend file etc. And it also made the zip package of the component a little bit bigger...
So now the language files are split. We have one for frontend and one for backend. Thanks to the joomla library we are able to load the backend file in the frontend so we can reuse the translation for emails etc...
If you find that the language file is incorrect, please fix it and send it back to us. I'll add it to the next release and this way all the community is going to profit.
Cheers,
Daniel