I would be very interested to see an actual double-blind test performed to see if people can even tell the difference. My guess is that most people will be able to tell the difference no better than mere chance. I say that because before this whole thing became a media sensation, no one was really making a big fuss because they never noticed a difference!
In post #461, you can read my short review of a taste test done by a Norwegian newspaper.
Here is the article, but you might want to learn Norwegian first..
And no, they really couldn't taste the difference.