Women's Boxing is one of the newest events and there are no new sports in the 2012 London Olympics
baseball and softball
26 Olympic sports, and 39 disciplines, in London 2012 Olympics - for Paralympics, it's 20 Sports in 21 disciplines. Source - London 2012 GamesMaker handbook.
302 in 26 sports
BMX was one of them.
gymnastics I think
There are 26 sports and 39 disciplines for the 302 events
There are 302 events in 26 sports for the 2012 London Olympics