Dear SS (re a previous conversation) - and others who might be contemplating visiting London this summer,
Though I'm not sure whether it constitutes a "travel-related" matter (in the conventional sense of the term), I nevertheless thought that the following piece (from a relatively reputable website) might be of interest:
"The Ministry of Defence is considering placing surface-to-air missiles on residential flats during the Olympics.
An east London estate, where 700 people live, has received leaflets saying a "Higher Velocity Missile system" could be placed on a water tower.
A spokesman said the MoD had not yet decided whether to deploy ground based air defence systems during the event."
Best of luck,