An easy way to keep up with changes in the original articles and to manage continuous contributions is to keep all translations in the translation project's Sources repository. That way, it is easy to edit draft translations and install them in ‘www’ only when they're ready. It is also convenient to update the translation (merge any changes from the original) while it is still under review.
See PO Files and Team, for more information.
Remember: A choice of a particular VCS is a sensitive matter—some modern ones provide compelling features, but they also bump the barrier for participation higher. The VCS is supposed to ease collaborative maintenance—if it eases only you, project members just won't use so that won't be a net win.
An alternative way to maintain translations is to use one of the existing online editors. There are plans to install a web-based system for managing .po files at Savannah, including online editing and statistics. Until it happens, teams who wish to use this functionality may setup such a server on a host of their own, or use one of the existing free hosting platforms such as Launchpad (http://translations.launchpad.net).
Here is a short and probably incomplete list of such systems:
If you decide to use such a system, please make sure that no translations are published in HTML format there.
Note that to keep the .pot files regularly updated (assuming such a web-based system runs msgmerge automatically), you'll have to take care of the one-way regular sync from the ‘www’ CVS repository.