Well some of this stuff is true. In London there are over 1400 accredited photographers. The process starts over a year before the Olympics start. Each country is issued a certain number of photos accredications, the majority are "all access", which means that the photographers are able to shoot in every venue. They do issue sport specfic accreditation as well, if someone just wants to shoot equestrian, they are issued a pass that gets them into the equestrian venue, and the media centre.
Space is somewhat limited, and in most cases, as in track, it is a first come best spot, which is why photographers will camp overnight for the prime spots, they shoot from the moat that runs around the track. There are a certain number of infield spots avaliable to the wire services and agency photographers, for track it is between 12-16 spots, these are the guys you see running around on the track after the races. For events like swimming, each counrty is given a certain number of tickets based on the number of swimmers they have in the finals, for the heats, it's open to first come. If Canada has a swimmer in the final they are given more tickets than a country that has no swimmers. Sometimes the tickets have seat numbers and sometimes it is first come again. There is also a pool postion for the wire services and agencies.
Photographers can also use any empty seat in the stands, but must move if the spectator shows up, also can't block any spectators or they are asked to leave, it's understood in the photographers rule handbook that is given out.
Opening and closing ceremonies are all ticketed events even with an accreditation.
It is possible for a freelance photographer to get an accrediatation to the Olympics, but very difficult, it is up to each country to decide.
As an example of another way around it, and if you have connections, I couldn't get an accreditation though the Canadian Olympic Association for Bejing, but I was offered one from Australia because I knew the right people. Connections help, but I chose not to go.
Canon and Nikon both have free loan services in the main press centre, or at least they used to, accredited photographers had access to all the gear, including dropping off their own gear for free service for cleaning and repairs.
Hope this helps.