I think until we end up with a "virtual reality" system like that in the movie "Surrogates" (where basically everyone lays at home and drives around these humanoid robots, but they still experience sensation and such without actually being there), I don't think that the Internet and TV will have much negative effect on tourism. On the other hand, one could argue that the internet and TV promote tourism, due to all the advertising and travel shows we are bombarded with.