It's bound to be very hectic but very exciting! I went to the 1996 Atlanta games, and it was an amazing experience. The city was transformed with barricades, port-a-johns, and vendor booths. All in all, it was very clean, neat, and organized! But I've never seen so many pedestrians in my life! At lunchtime every day, there was a two-hour wait for just about every restaurant downtown. (That's why there were so many vendors selling burgers, etc. on the sidewalks.)
As a spectator/tourist, I loved the Olympic experience - but I don't think I envy you, purrley, as a resident who will have your live thrown off-balance for a few weeks!