They definitely don't "reveal all the secrets of the A380" (as if), but it is interesting and the facility is staggeringly large (second largest by volume and sixth by floor area in the world).
I visited the Saint-Nazaire factory two years ago. It's absolutely amazing how you go by dozens of A320, and just at the end of the tour we went by the massive A380. The difference in size at ground level is stunning.
They definitely don't "reveal all the secrets of the A380" (as if), but it is interesting and the facility is staggeringly large (second largest by volume and sixth by floor area in the world).