Translations were generally approved by one of us at Automattic, but we can only validate so much as we don’t speak all the languages (we try, though!), so that we now support “validator” profiles on GlotPress, for those users who want to help out in semantic and consistency validation (and not just technical). If you feel this is something you might want to sink your teeth into, please drop us a line in the forums.
I’m sorry. I did not click the forums link in the announcement and erroneously assumed it was a link to the International forums. In fact it was to this “Translations” forum which I didn’t realize existed here in the English speaking wordpress.com forums. I apologize for any confusion I caused. :(