I think the easy way to explain it is - organic wine making taken to the extreme, no chemical pesticides, fungicides or herbicides, but that is just the start, growers will use natural preparations in the vineyards including quartz and ground cow horn. Let me explain this ritual, take one cow horn along with horse manure and horn silica, dilute them in water stir for one hour first in one direction then the other for a further hour, the solution can then be either sprayed on the vines or applied to the ground as a compost together with nettles, oak bark and dandelion.
All this needs to be done at the correct time as the vines are all influenced by the sun, moon, stars and planets, the planting season is organised according to the Maria Thun planting calender, this divides the year into root, leaf, fruit and flower days, planting, pruning and harvesting all need to be done not only on the right day but at the right time of day.
It is difficult to believe that the arrangement of the stars & planets could have such a direct effect on a bottle of wine.
I think over the coming 12 months you will here more and more about biodynamic wine making and the media gets more interested.
I have had the pleasure on a number of occasions to try some of these wines and they were indeed very nice, it is difficult to know whether or not they were better for being made this way.
You will normally find that this method of wine production would only be used for medium and high priced wines as the labour costs involved are quite high. People within the industry better qualified than I have said to me "I know it seems as if this is all some kind of alchemy, but it does seem to work". Remember you heard it hear first.............
"In a progressive country change is constant; ...change... is inevitable."