Included in the clarifications, additional verbiage was added to the regulations constituting an illegal strike to the back of a competitor's head. The revised rules now distinguish the back of the head as the "crown of the head down the centerline of the skull into the spine, with a one-inch variance to each side." This is commonly referred to as the "Mohawk" definition.
In addition, verbiage prohibiting elbow strikes in the downward "12-to-6 o'clock" motion was stricken, as the original rule's intention was to prohibit the technique to the restricted spinal cord area, not ban the actual movement itself. Elbow strikes of all kinds are permissible, except to illegal areas.
Smothering the mouth or nose of an opponent has been added to the Unified Rules' fouls list, prohibiting a fighter from using his hand to prevent his opponent's ability to breathe. According to the new verbiage, this does not include choke attempts where a fighter's mouth is covered by his opponent's arm.
An amendment to include knees to the head of a downed opponent was not part of the revised regulations.
Fourteen weight classes are now defined in the men's division under the Unified Rules, beginning at the 105-pound flyweight division and moving up in 10-pound increments to super heavyweight at 265 pounds and over. In particular, the welterweight division will now range from 165-175 pounds, while light heavyweight fighters will be specified between 205-225 pounds. Heavyweight entrants will be asked to weigh in between 225-265 pounds.
Promotions will not be required to adopt the new weight divisions. However, if they do not, they will not be following Unified Rules.
Nothing too big.
Nice to have clarification on strikes to the back of the head and downward elbows, but we'll see how they are put into play by the refs.
The weight class changes are kind of interesting though. If I understand the article correctly, these would be the upper limit for each weightclass (not sure about names for all of them).
105
115
125
135
145
155 - Lightweight?
165 - Lightweight?
175 - Welterweight
185 - Middleweight?
195
205
225 - Light Heavyweight
265 - Heavyweight
265+ - Super Heavyweight
It will be interesting to see if the UFC adopts these changes. I think it would be for the best, as pretty much every fighter could be fighting at their optimal weight. On the other hand, it could dilute the competition at each weight class a bit, and/or create some confusion with fighters crossing over between multiple weight classes. Could work for the UFC though, as they could have at least one championship fight at practically every event. I guess the easy way around it would be to just not have fights at the weight classes they don't want (ie/ 195, maybe 165 and 225), as I think that would still be following the unified rules.