It would do the following:
- set some userss as translaters in the acp
- set a switch for those users in there ucp to go into translation-mode
- if this user enters the site he sees a small edit-button after every phrase.
- the color of the button shows if a phrase is translated.
- maybe red to signal an untranslated phrase
- clicking on a button makes it possible to instantly translate
- inline would be ultimate