Screw tops are better. Tighter, less oxygen, easier to deal with, and they don't ever rot. If you ever get a glass of wine that smells intensely rotten it could be because the cork has started rotting.
For wines that lose their primary characteristic when aged (think fruity, fresh wines, normally whites) a screw top is the way to go, for something you want to keep in your cellar and let it evolve a bit till is just right, I'll take cork every day.
As a sidenote, cork was one of the main components of the Space Shuttle's insulation (http://www.nytimes.com/1981/11/03/science/shuttle-s-cork-fro...) [and yes, I'm from Portugal, you can all blame us for the Columbia...]
Overall, a screw-cap is a way better option, one of the biggest wine vendors in France (Chateau Bonnet from the famous André Lurton) switched to caps some years ago after extensive research and also prefers them above traditional cork for all wines. Furthermore see [2], they list the following advantages:
- No cork taint
- No more sporadic oxidation
- Screwcaps avoid flavour modification, including scalping
- Both red and white wines can age under screwcap
- A reliable long-term seal
- Cellaring
- Recycling
[1] http://www.mutineermagazine.com/blog/2008/05/screw-this-cap-...
[2] http://www.screwcapinitiative.com/normal.asp?navID=24&pa...
Theoretically cork taint is mostly avoidable as long as the wines aren't stored in buildings made from wood or that have wood floors, and as long as there isn't air conditioning. The reason for cork taint is that the chlorine that's used in cleaning products and that comes out of air conditioners (running on chlorinated city water) builds up in wood over time, and then reacts with the mold in cork to form TCA. The other problem is that the vast majority of cork is stored on the ground and is just left to get moldy with zero quality standards, despite what this article would have you believe. Cork taint should be essentially non-existant up until the time of purchase, it's just that the industry has been completely unable to get its act together.
Very curious - thanks for the insight, esp on the cleaning products!
Wine is often a social experience - so there is something too be said for the "fun" and flash of popping open a cork.
In a similar note, we have a "rabbit" corkscrew. It's super efficient at opening a bottle, but is not particularly satisfying. Have you ever asked yourself, If only I could open this bottle faster? (Although it can be convenient if you're cooking with wine.)
I bet that, once you get used to it (after spoling a few hundreds of corks, that's it) it's faster than the "rabbit" model.
I say that because I used to be faster with the simple, T-shaped screw, and I've seen it used in restaurants by experienced waiters.