On tourism, at least one critique ive read suggests it will have neutral-10% increase on tourism, as the olympics will simply displace existing tourists. As for the future of tourism in london, why are people going to come here to see a stadium? They come here (already) to see Parliament, Buck Palace, the Tower etc. The promise of a great increase in Tourism is based on the experince of Barcelona a provincial city relatively unknown before the Olympics.
I think its a simple cup half full, cup half empty argument. People who see the world with a positive attitude want it, and the people who's cup runneth half empty don't.
Stop looking at the possible downside, because it's blocking out a truly wonderful opportunity for us all to have a party!