Of course it's not representative of the traveling public, but it was never supposed to be. Whether or not it's representative of FT, or of people who frequent Internet travel discussion groups, is a legitimate question - which I don't know of any practical way to answer.
It's kinda like surveying registered Republicans about what they think of Pres. Bush. The results are almost certainly not representative of U.S. voters overall, but can be interesting in their own right.
This is.