I'm not really sure if I think something bad will happen or not. I remember everyone panicking before the World Cup in South Africa that there would be riots, and it was a peaceful party. I don't think the Sotchi Olympics will be remembered as a peaceful party though. These sports events are taking place in more and more dangerous locations because of profits and the countries' lobbywork. Something is bound to happen and sadly, it won't be surprising.

Did you even read it. It's an advisory, not a warning. It's basically telling its citizens to remain cautious, and that the government is unsure about the safety.

Sochi has NEVER hosted such a large scale events, so basically its possibly not even equiped to handle large scale crowds, so if an incident were to happen its hospitals and clinics could be overwhelmed.

Also, security is/has been a concern for a while for these games. It's all very sketchy and unknown at this point.