Anthony Johnson vs. Kevin Burns.  Mirko CroCop vs. Mustapha Al Turk.  Nick Thompson vs. Tim Kennedy. If any of those fights ring a bell, the most likely reason was the controversy associated with the outcome.  Inadvertent pokes to the eye disguised as punches were the culprit for the first two, and illegal strikes to a downed opponent was the argument in Thompson vs. Kennedy, which was exclusively discussed by Nick Thompson in this interview on TheGarv.com. These events fueled the Nevada State Athletic Commission to propose the implementation of instant replay to the sport of MMA.  Before the football fans jump out of their chairs to complain about how this will bring the momentum of the contest to a painful halt, the rules stipulate that the tape will be reviewed immediately after the fight.  Here's the summary as reported by MMAJunkie.com:

A referee may view a replay, if available, at the conclusion of a contest or exhibition stopped immediately due to an injury to an unarmed combatant pursuant to NAC 467.718 in order to determine whether the injury in question was caused by a legal blow or a foul.

If an illegal blow or foul was the cause of the injury, the referee will then arbitrate the intention of the fighter who committed the foul.  If the foul was inadvertent, a No Contest will be rendered- if intentional, a DQ will result.  Another additional item on the docket stems from the "Greasegate" scandal involving B.J. Penn's claim that Georges St. Pierre had an excessive amount of grease wiped all over his body by his corner, which eliminates the necessary friction to execute submission techniques.  This is the proposed new restriction:

Applying any foreign substance to the hair or body that could result in an advantage.

Personally, I applaud Keith Kizer and the NSAC for their commitment to evolution and improvement.  The Johnson/Burns and CroCop/Al Turk results were definitively and without question due to an inadvertent yet completely illegal poke to the eye.  The Thompson/Kennedy fight was debatable, but at least it will be reviewed and put to rest by the officials in the future should the rule be instated.