I have just enabled creation of "LATEST" links for PO compendiums. The result is that now you can use an automated tool or kbabel to get the latest compendium made from po-debconf translations of packages in unstable.
So your compendium will be in the place like http://i18n.debian.net/~eddyp/compendiums/po/$LANG/compendium-$LANG-LATEST.po
I have took a series of screenshots that show how to configure kbabel in order to use the compendium, but I didn't managed to write some explanations, too.
Screenshots are here (just pick them in order, and you'll probably understand).
The most important are the first 3.
An explanation about step 3, if you defined the language code properly, then you can use the flexible approach:
Otherwise, you need to use a hard coded URL.