MMA was actually one of the first sports to be featured in the Olympics. Back then it was called "Pankration" by the Greeks. It was introduced in the Greek Olympic games in 648 BC. The sport was a mix of both wrestling and boxing. Both of which were part of the games as well.
Read the Wiki on it. It is very interesting:
http://en.wikipedia.org/wiki/Pankration
I agree with J Rock, MMA should be in the Olympics, it is one sports that is practiced world-wide. Every corner of the globe has MMA competitions, or at least something like it with modified rules that mix striking with wrestling.