@ Ryan, am seriously looking at going, especially after what you wrote above. Do you think the visa and travel rules are the same for Poms? I tend to pick and chose which passport to use. My kiwi one sounds like a wee bit of a hassle.
A NZ passport is fine to travel on, although I did cause some consternation when crossing into China in the far east. They were sure it was a fake as they only ever had russian and Chinese nationals crossing at that point. With a Kiwi passport you have the added benefit of going into the world queue rather than the European queue if transiting in Europe, which is always much shorter.
As far as ultras go, I'm sure the police and military will be out in force. It's also a prime target for terrorists from Chechnya or Dagestan and they don't want trouble in such a high profile event. I wouldn't worry about people rioting personally, keep an eye open for it and don't be a prick and antagonise people, but you'd be unlucky to be caught in it.
You do need to keep an eye out for Russia's robot uprising though: