Hmm. I live very close to Mercurey and I have never seen a screw top wine there or anywhere in Burgundy for that matter. However I am sure that the primary argument for staying traditional with cork is not scientific. It is just that it is what the customers want.

Like gfunkdave, when I open a bottle that has a synthetic cork, I just feel like this must be an inferior wine.

When it comes to "new world" wines however, I don't have a problem with the screw top. I've had some perfectly fine Aussie wines with screw tops. However the real top of the line Barossa wines (my favorite Aussie region) have always used cork. Grant Burge is the best of the bunch there.

And there is such a thing as screw top reduction. I saw something that said 2.2% of screw top wines suffer from this.